Disposable article having sensor to detect impending elimination of bodily waste

ABSTRACT

A disposable article to be fitted to a wearer. The disposable article preferably comprises a sensor operatively connected to the article. The sensor is adapted to detect electrical activity in the wearer&#39;s smooth colonic muscles, abdominal muscles or the muscles surrounding the bladder or rectum which correlates to an impending elimination of bodily waste and to provide a signal to the wearer, a caregiver or an element of the article of the impending event.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of prior application U.S.Ser. No. 09/342,784 filed on Jun. 29, 1999, which is acontinuation-in-part of prior application U.S. Ser. No. 09/107,561 filedon Jun. 29, 1998, U.S. Pat. No. 6,149,636 and U.S. Ser. No. 09/106,225filed on Jun. 29, 1998, U.S. Pat. No. 6,186,149 and a non-provisionalfiling of prior provisional application U.S. Ser. No. 60/090,993 filedJun. 29, 1998. This application is also a continuation-in-part of U.S.Ser. No. 09/342,289 filed on Jun. 29, 1999, now U.S. Pat. No. 6,266,557which is a continuation-in-part of prior application U.S. Ser. No.09/107,561 filed on Jun. 29, 1998 now U.S. Pat. No. 6,149,636.

FIELD OF THE INVENTION

The present invention relates to disposable articles and, moreparticularly, to disposable articles having a sensor adapted to detectan input that correlates to an impending elimination of bodily waste andto provide a signal to the wearer of the article of such impendingevent.

BACKGROUND OF THE INVENTION

Today, disposable articles, such as diapers, pants-type diapers,training pants, adult incontinence briefs, sanitary napkins and tampons,are widely used in infant and toddler care and in the care of-incontinent adults as a means of containing, isolating and disposing ofbodily wastes. These articles have generally replaced reusable, washablecloth garments as the preferred means for these applications because oftheir convenience and reliability. The disposable articles respond to adefecation, urination or discharge event by absorbing or containingbodily wastes deposited on the article. Some disposable articles alsosignal a defecation, urination or discharge event after it has occurred(e.g., wetness indicators, temperature change detection). The articles,however, do not predict when an event is about to occur and prepare thearticle, wearer or caregiver for the occurrence of the predicted event.Current disposable articles have absorbent material in a configurationready for use at the time of application to the wearer or have aconfiguration that does not become available until the time of adischarge of bodily waste or shortly thereafter. Barrier cuffs, forexample, are in position when the article is applied to the wearer.Signaling devices such as thermal or visual indicators or nocturnalenuresis alarms signal a urination event only after the urination hasbegun. For example, known potty training devices, however, detect andsignal the wearer once the defecation or urination has begun and do notgive the wearer the ability to get to the bathroom in time to prevent anaccident or bedwetting.

SUMMARY OF THE INVENTION

The present invention is directed to a disposable article to be fittedto a wearer. The disposable article preferably comprises a sensoroperatively connected to the article. The sensor is adapted to detectelectrical activity in the wearer's smooth colonic muscles, abdominalmuscles, muscles surrounding the wearer's bladder or muscles surroundingthe wearer's rectum which correlates to an impending elimination ofbodily waste and to provide a signal to the wearer, a caregiver or anelement of the article of the impending event.

The present invention also includes an article which includes a sensoradapted to detect hen a body cavity of the wearer reaches apredetermined volume and a signal mechanism which provides a signal tothe wearer, a caregiver or an element of the article once thepredetermined body cavity volume has been reached.

The invention also includes methods for helping an incontinent personachieve a temporary contraction of a sphincter muscle by stimulating themuscle in response to a detected impending elimination of bodily waste.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an article made in accordance with the presentinvention in a flat-out state with portions of the structure beingcut-away to more clearly show the construction of the article, whereinthe article is a diaper.

FIG. 2 is a perspective view of a waste bag embodiment of the presentinvention.

FIG. 3 is a perspective view of one embodiment of a diaper whichincludes a waste bag.

FIG. 4 shows a diagram of an absorbent article embodiment of theapparatus of the present invention.

FIG. 5 shows a perspective view of a bodily waste isolation device ofthe present invention in a compressed state before activation.

FIG. 5A shows a sectional view taken along line 5A—5A of FIG. 2.

FIGS. 6A and 6B show an embodiment of a responsive system of the presentinvention including an electrically sensitive gel.

FIGS. 7A, 7B and 7C show another embodiment of a responsive system ofthe present invention including an electrically sensitive gel.

FIG. 8A shows an ideal output function of a discontinuous responsivesystem of the present invention having a single threshold level.

FIG. 8B shows an ideal output function of a discontinuous responsivesystem of the present invention having multiple threshold levels.

FIG. 9A shows an exemplary output function of a discontinuous responsivesystem of the present invention along with the first, second and thirdderivatives of the output function.

FIG. 9B shows a transfer function of a control system having a series offirst order lags having an equal time constant.

FIG. 10A shows a block diagram of an exemplary open loop responsivesystem.

FIG. 10B shows a block diagram of an exemplary closed loop responsivesystem.

FIG. 10C shows a block diagram of an exemplary open loop responsivesystem including a controller.

FIG. 10D shows a block diagram of an exemplary closed loop responsivesystem including a controller.

FIG. 11A is a graphical example of an increase in the basal electricalactivity of an external anal sphincter muscle related to defecation.

FIG. 11B is an graphical example of a decrease in the basal electricalactivity of an external anal sphincter muscle related to defecation.

FIG. 12 shows a diagram of a belt comprising sensors arranged so as todetect electrical activity in the wearer's colonic or abdominal wallmuscles.

FIGS. 13A-13E are graphical examples of how a high amplitude propagatingcontraction of the smooth muscle along a human colon plotted over time.

FIG. 14 is a graphical representation of the electrical activitymeasured at a wearer's skin surface above a portion of the wearer'scolon as well as a measurement of the pressure inside the colon.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term “absorbent article” refers to devices whichabsorb and contain body exudates, and more specifically, refers todevices which are placed against or in proximity to the body of thewearer to absorb and contain the various exudates discharged from thebody. The term “disposable” is used herein to describe absorbentarticles which generally are riot intended to be laundered or otherwiserestored or reused as an absorbent article (i.e., they are intended tobe discarded after a single use and, preferably, to be recycled,composted or otherwise disposed of in an environmentally compatiblemanner). A “unitary” absorbent article refers to absorbent articleswhich are formed of separate parts united together to form a coordinatedentity so that they do not require separate manipulative parts like aseparate holder and liner. A preferred embodiment of an absorbentarticle of the present invention is a unitary disposable absorbentarticle, such as the diaper 20 shown in FIG. 1. As used herein, the term“diaper” refers to an absorbent article generally worn by infants andincontinent persons about the lower torso. The present invention is alsoapplicable to other absorbent or non-absorbent articles such asincontinence briefs, incontinence undergarments, absorbent inserts,diaper holders and liners, colostomy bags for a natural or artificialanus, feminine hygiene garments, tampons, wipes, disposable towels,tissues, water absorbing articles, oil absorbing articles, spill cleanupbags, desiccant bags, disposable mops, bandages, therapeutic wraps,supports, disposable heating pads and the like.

FIG. 1 is a plan view of the diaper 20 of the present invention in aflat-out, state with portions of the structure being cut-away to moreclearly show the construction of the diaper 20. The portion of thediaper 20 which faces the wearer is oriented towards the viewer. Asshown in FIG. 1, the diaper 20 preferably comprises a liquid pervioustopsheet 24; a liquid impervious backsheet 26; an absorbent core 28,which is preferably positioned between at least a portion of thetopsheet 24 and the backsheet 26; side panels 30; elasticized leg cuffs32; an elastic waist feature 34; and a fastening system generallydesignated 40. Diaper 20 is shown in FIG. 1 to have a first waist region36, a second waist region 38 opposed to the first waist region 36 and acrotch region 37 located between the first waist region and the secondwaist region. The periphery of the diaper 20 is defined by the outeredges of the diaper 20 in which the longitudinal edges 50 run generallyparallel to the longitudinal centerline 100 of the diaper 20 and the endedges 52 run between the longitudinal edges 50 generally parallel to thelateral centerline 110 of the diaper 20.

The chassis 22 of the diaper 20 comprises the main body of the diaper20. The chassis 22 comprises at least a portion of the absorbent core 28and preferably an outer covering layer including the topsheet 24 and thebacksheet 26. If the absorbent article comprises a separate holder and aliner, the chassis 22 generally comprises the holder and the liner. (Forexample, the holder may comprise one or more layers of material to formthe outer cover of the article and the liner may comprise an absorbentassembly including a topsheet, a backsheet, and an absorbent core. Insuch cases, the holder and/or the liner may include a fastening elementwhich is used to hold the liner in place throughout the time of use.)For unitary absorbent articles, the chassis 22 comprises the mainstructure of the diaper with other features added to form the compositediaper structure. While the topsheet 24, the backsheet 26, and theabsorbent core 26 may be assembled in a variety of well knownconfigurations, preferred diaper configurations are described generallyin U.S. Pat. No. 3,860,003 entitled “Contractible Side Portions forDisposable Diaper” which issued to Kenneth B. Buell on Jan. 14, 1975;U.S. Pat. No. 5,151,092 issued to Buell on Sep. 9, 1992; and U.S. Pat.No. 5,221,274 issued to Buell on Jun. 22, 1993; and U.S. Pat. No.5,554,145 entitled “Absorbent Article With Multiple Zone StructuralElastic-Like Film Web Extensible Waist Feature” which issued to Roe etal. on Sep. 10, 1996; U.S. Pat. No. 5,569,234 entitled “DisposablePull-On Pant” which issued to Buell et al. on Oct. 29, 1996; U.S. Pat.No. 5,580,411 entitled “Zero Scrap Method For Manufacturing Side PanelsFor Absorbent Articles” which issued to Nease et al. on Dec. 3, 1996;and U.S. patent application Ser. No. 08/915,471 entitled “AbsorbentArticle With Multi-Directional Extensible Side Panels” filed Aug. 20,1997 in the name of Robles et al.; each of which is incorporated hereinby reference.

The backsheet 26 is generally that portion of the diaper 20 positionedadjacent the garment facing surface 45 of the absorbent core 28 whichprevents the exudates absorbed and contained therein from soilingarticles which may contact the diaper 20, such as bedsheets andundergarments. In preferred embodiments, the backsheet 26 is imperviousto liquids (e.g., urine) and comprises a thin plastic film such as athermoplastic film having a thickness of about 0.012 mm (0.5 mil) toabout 0.051 mm (2.0 mils). Suitable backsheet films include thosemanufactured by Tredegar Industries Inc. of Terre Haute, Ind. and soldunder the trade. names X15306, X10962 and X10964. Other suitablebacksheet materials may include breathable materials which permit vaporsto escape from the diaper 20 while still preventing exudates frompassing through the backsheet 26. Exemplary breathable materials mayinclude materials such as woven webs, nonwoven webs, composite materialssuch as film-coated nonwoven webs, and microporous films such asmanufactured by Mitsui Toatsu Co., of Japan under the designation ESPOIRNO and by EXXON Chemical Co., of Bay City, Tex., under the designationEXXAIRE. Suitable breathable composite materials comprising polymerblends are available from Clopay Corporation, Cincinnati, Ohio under thename HYTREL blend P18-3097. Such breathable composite materials aredescribed in greater detail in PCT Application No. WO 95/16746,published on Jun. 22, 1995 in the name of E. I. DuPont and copendingU.S. Pat. No. 5,865,823 issued to Curro on Feb. 2, 1999. Otherbreathable backsheets including nonwoven webs and apertured formed filmsare described in U.S. Pat. No. 5,571,096 issued to Dobrin et al. on Nov.5, 1996. Each of these references is hereby incorporated by referenceherein.

The backsheet 26, or any portion thereof, may be elastically extensiblein one or more directions. In one embodiment, the backsheet 26 maycomprise a structural elastic-like film (“SELF”) web. A structuralelastic-like film web is an extensible material that exhibits anelastic-like behavior in the direction of elongation without the use ofadded elastic materials. SELF webs suitable for the present inventionare more completely described in U.S. Pat. No. 5,518,801 entitled WebMaterials Exhibiting Elastic-Like Behavior, which issued to Chappell,et, al. on May 21, 1996, which is incorporated herein by reference. Inalternate embodiments, the backsheet 26 may comprise elastomeric films,foams, strands, or combinations of these or other suitable materialswith nonwovens or synthetic films.

The backsheet 26 may be joined to the topsheet 24, the absorbent core 28or any other element of the diaper 20 by any attachment means known inthe art. (As used herein, the term “joined” encompasses configurationswhereby an element is directly secured to another element by affixingthe element directly to the other element, and configurations whereby anelement is indirectly secured to another element by affixing the elementto intermediate member(s) which in turn are affixed to the otherelement.) For example, the attachment means may include a uniformcontinuous layer of adhesive, a patterned layer of adhesive, or an arrayof separate lines, spirals, or spots of adhesive. One preferredattachment means comprises an open pattern network of filaments ofadhesive as disclosed in U.S. Pat. No. 4,573,986 entitled “DisposableWaste-Containment Garment”, which issued to Minetola et al. on Mar. 4,1986. Other suitable attachment means include several lines of adhesivefilaments which are swirled into a spiral pattern, as is illustrated bythe apparatus and methods shown in U.S. Pat. No. 3,911,173 issued toSprague, Jr. on Oct. 7, 1975; U.S. Pat. No. 4,785,996 issued to Ziecker,et al. on Nov. 22, 1978; and U.S. Pat. No. 4,842,666 issued to Wereniczon Jun. 27, 1989. Each of these patents are incorporated herein byreference. Adhesives which have been found to be satisfactory aremanufactured by H. B. Fuller Company of St. Paul, Minn. and marketed asHL-1620 and HL-1358-XZP. Alternatively, the attachment means maycomprise heat bonds, pressure bonds, ultrasonic bonds, dynamicmechanical bonds, or any other suitable attachment means or combinationsof these attachment means as are known in the art.

The topsheet 24 is preferably positioned adjacent the body surface 47 ofthe absorbent core 28 and may be joined thereto and/or to the backsheet26 by any attachment means known in the art. Suitable attachment meansare described above with respect to means for joining the backsheet 26to other elements of the diaper 20. In one preferred embodiment of thepresent invention, the topsheet 24 and the backsheet 26 are joineddirectly to each other in some locations and are indirectly joinedtogether in other locations by directly joining them to other elementsof the diaper 20.

The topsheet 24 is preferably compliant, soft feeling, andnon-irritating to the wearer's skin. Further, at least a portion of thetopsheet 24 is liquid pervious, permitting liquids to readily penetratethrough its thickness. A suitable topsheet 24 may be manufactured from awide range of materials, such as porous foams; reticulated foams;apertured plastic films; or woven or nonwoven webs of natural fibers(e.g., wood or cotton fibers), synthetic fibers (e.g., polyester orpolypropylene fibers), or a combination of natural and synthetic fibers.If the topsheets include fibers, the fibers may be spunbond, carded,wet-laid, meltblown, hydroentangled, or otherwise processed as is knownin the art. One suitable topsheet 24 comprising a web of staple lengthpolypropylene fibers is manufactured by Veratec, Inc., a Division ofInternational Paper Company, of Walpole, Mass. under the designationP-8.

Suitable formed film topsheets are described in U.S. Pat. No. 3,929,135,entitled “Absorptive Structures Having Tapered Capillaries”, whichissued to Thompson on Dec. 30, 1975; U.S. Pat. No. 4,324,246 entitled“Disposable Absorbent Article Having A Stain Resistant Topsheet”, whichissued to Mullane, et al. on Apr. 13, 1982; U.S. Pat. No. 4,342,314entitled “Resilient Plastic Web Exhibiting Fiber-Like Properties”, whichissued to Radel, et al. on Aug. 3, 1982; U.S. Pat. No. 4,463,045entitled “Macroscopically Expanded Three-Dimensional Plastic WebExhibiting Non-Glossy Visible Surface and Cloth-Like TactileImpression”, which issued to Ahr, et al. on Jul. 31, 1984; and U.S. Pat.No. 5,006,394 “Multilayer Polymeric Film” issued to Baird on Apr. 9,1991. Other suitable topsheets 30 are made in accordance with U.S. Pat.Nos. 4,609,518 and 4,629,643 which issued to Curro et al. on Sep. 2,1986 and Dec. 16, 1986, respectively, and both of which are incorporatedherein by reference. Such formed films are available from The Procter &Gamble Company of Cincinnati, Ohio as “DRI-WEAVE” and from TredegarCorporation of Terre Haute, Ind. as “CLIFF-T.”

Preferably, the topsheet 24 is made of a hydrophobic material or istreated to be hydrophobic in order to isolate the wearer's skin fromliquids contained in the absorbent core 28. If the topsheet 24 is madeof a hydrophobic material, preferably at least the upper surface of thetopsheet 24 is treated to be hydrophilic so that liquids will transferthrough the topsheet more rapidly. This diminishes the likelihood thatbody exudates will flow off the topsheet 24 rather than being drawnthrough the topsheet 24 and being absorbed by the absorbent core 28. Thetopsheet 24 can be rendered hydrophilic by treating it with a surfactantor by incorporating a surfactant into the topsheet. Suitable methods fortreating the topsheet 24 with a surfactant include spraying the topsheet24 material with the surfactant and immersing the material into thesurfactant. A more detailed discussion of such a treatment andhydrophilicity is contained in U.S. Pat. No. 4,988,344 entitled“Absorbent Articles with Multiple Layer Absorbent Layers” issued toReising, et al. on Jan. 29, 1991 and U.S. Pat. No. 4,988,345 entitled“Absorbent Articles with Rapid Acquiring Absorbent Cores” issued toReising on Jan. 29, 1991. A more detailed discussion of some suitablemethods for incorporating surfactant in the topsheet can be found inU.S. Statutory Invention Registration No. H1670, published on Jul. 1,1997 in the names of Aziz et al. Each of these references is herebyincorporated by reference herein. Alternatively, the topsheet 24 mayinclude an apertured web or film which is hydrophobic. This may beaccomplished eliminating the hydrophilizing treatment step from theproduction process and/or applying a hydrophobic treatment to thetopsheet 24, such as a polytetraflouroethylene compound like SCOTCHGUARDor a hydrophobic lotion composition, as described below. In suchembodiments, it is preferred that the apertures be large enough to allowthe penetration of aqueous fluids like urine without significantresistance.

Any portion of the topsheet 24 may be coated with a lotion as is knownin the art. Examples of suitable lotions include those described in U.S.Pat. Nos. 5,607,760 entitled “Disposable Absorbent Article Having ALotioned Topsheet Containing an Emollient and a Polyol PolyesterImmobilizing Agent” which issued to Roe on Mar. 4, 1997; U.S. Pat. No.5,609,587 entitled “Diaper Having A Lotion Topsheet Comprising A LiquidPolyol Polyester Emollient And An Immobilizing Agent” which issued toRoe on Mar. 11, 1997; U.S. Pat. No. 5,635,191 entitled “Diaper Having ALotioned Topsheet Containing A Polysiloxane Emollient” which issued toRoe et al. on Jun. 3, 1997; and U.S. Pat. No. 5,643,588 entitled “DiaperHaving A Lotioned Topsheet” which issued to Roe et al. on Jul. 1, 1997.The lotion may function alone or in combination with another agent asthe hydrophobizing treatment described above. The topsheet may alsoinclude or be treated with antibacterial agents, some examples of whichare disclosed in PCT Publication No. WO 95/24173 entitled “AbsorbentArticles Containing Antibacterial Agents in the Topsheet For OdorControl” which was published on Sep. 14, 1995 in the name of TheresaJohnson. Further, the topsheet 24, the backsheet 26 or any portion ofthe topsheet or backsheet may be embossed and/or matte finished toprovide a more cloth like appearance.

The absorbent core 28 may comprise any absorbent material which isgenerally compressible, conformable, non-irritating to the wearer'sskin, and capable of absorbing and retaining liquids such as urine andother certain body exudates. The absorbent core 28 may be manufacturedin a wide variety of sizes and shapes (e.g., rectangular, hourglass,“T”-shaped, asymmetric, etc.) and may comprise a wide variety ofliquid-absorbent materials commonly used in disposable diapers and otherabsorbent articles such as comminuted wood pulp, which is generallyreferred to as airfelt. Examples of other suitable absorbent materialsinclude creped cellulose wadding; meltblown polymers, including. coform;chemically stiffened, modified or cross-linked cellulosic fibers;tissue, including tissue wraps and tissue laminates; absorbent foams;absorbent sponges; superabsorbent polymers; absorbent gelling materials;or any other known absorbent material or combinations of materials.

The configuration and construction of the absorbent core 28 may also bevaried (e.g., the absorbent core(s) or other absorbent structure(s) mayhave varying caliper zones, a hydrophilic gradient, a superabsorbentgradient, or lower average density and lower average basis weightacquisition zones; or may comprise one or more layers or structures).However, the total absorbent capacity of the absorbent core 28 should becompatible with the design loading and the intended use of the diaper20.

Exemplary absorbent structures for use as the absorbent assemblies aredescribed in U.S. Pat. No. 4,610,678 entitled “High-Density AbsorbentStructures” issued to Weisman et al. on Sep. 9, 1986; U.S. Pat. No.4,673,402 entitled “Absorbent Articles With Dual-Layered Cores” issuedto Weisman et al. on Jun. 16, 1987; U.S. Pat. No. 4,834,735, entitled“High Density Absorbent Members Having Lower Density and Lower BasisWeight Acquisition Zones”, issued to Alemany et al. on May 30, 1989;U.S. Pat. No. 4,888,231 entitled “Absorbent Core Having A Dusting Layer”issued to Angstadt on Dec. 19, 1989; U.S. Pat. No. 5,137,537 entitled“Absorbent Structure Containing Individualized, Polycarboxylic AcidCrosslinked Wood Pulp Cellulose Fibers” which issued to Herron et al. onAug. 11, 1992; U.S. Pat. No. 5,147,345 entitled “High EfficiencyAbsorbent Articles For Incontinence Management” issued to Young et al.on Sep. 15, 1992; U.S. Pat. No. 5,342,338 entitled “Disposable AbsorbentArticle For Low-Viscosity Fecal Material” issued to Roe on Aug. 30,1994; U.S. Pat. No. 5,260,345 entitled “Absorbent Foam Materials ForAqueous Body Fluids and Absorbent Articles Containing Such Materials”issued to DesMarais et al. on Nov. 9, 1993; U.S. Pat. No. 5,387,207entitled “Thin-Until-Wet Absorbent Foam Materials For Aqueous BodyFluids And Process For Making Same” issued to Dyer et al. on Feb. 7,1995; and U.S. Pat. No. 5,625,222 entitled “Absorbent Foam Materials ForAqueous Fluids Made From high Internal Phase Emulsions Having Very HighWater-To-Oil Ratios” issued to DesMarais et al. on Jul. 22, 1997. Eachof these patents is incorporated herein by reference.

The diaper 20 may also comprise at least one elastic waist feature 34that helps to provide improved fit and containment. The elastic waistfeature 34 is generally intended to elastically expand and contract todynamically fit the wearer's waist. The elastic waist feature 34preferably extends at least longitudinally outwardly from at least onewaist edge 62 of the absorbent core 28 and generally forms at least aportion of the end edge 52 of the diaper 20. Disposable diapers areoften constructed so as to have two elastic waist features, onepositioned in the first waist region 36 and one positioned in the secondwaist region 38. Further, while the elastic waist feature 34 or any ofits constituent elements may comprise one or more separate elementsaffixed to the diaper 20, the elastic waist feature 34 may beconstructed as an extension of other elements of the diaper 20, such asthe backsheet 26, the topsheet 24, or both the backsheet 26 and thetopsheet 24.

The elastic waist feature 34 may be constructed in a number of differentconfigurations including those described in U.S. Pat. No. 4,515,595issued to Kievit et al. on May 7, 1985; U.S. Pat. No. 4,710,189 issuedto Lash on Dec. 1, 1987; U.S. Pat. No. 5,151,092 issued to Buell on Sep.9, 1992; and U.S. Pat. No. 5,221,274 issued to Buell on Jun. 22, 1993.Other suitable waist configurations may include waistcap features suchas those described in U.S. Pat. No. 5,026,364 issued to Robertson onJun. 25, 1991 and U.S. Pat. No. 4,816,025 issued to Foreman on Mar. 28,1989. All of the above mentioned references are incorporated herein byreference.

The diaper 20 may also include a fastening system 40. The fasteningsystem 40. preferably maintains the first waist region 36 and the secondwaist region 38 in an overlapping configuration so as to provide lateraltensions about the circumference of the diaper 20 to hold the diaper 20on the wearer. The fastening system 40 preferably comprises tape tabsand/or hook and loop fastening components, although any other knownfastening means are generally acceptable. Some exemplary fasteningsystems are disclosed in U.S. Pat. No. 3,848,594 entitled “TapeFastening System for Disposable Diaper” issued to Buell on Nov. 19,1974; B1 U.S. Pat. No. 4,662,875 entitled “Absorbent Article” issued toHirotsu et al. on May 5, 1987; U.S. Pat. No. 4,846,815 entitled“Disposable Diaper Having An Improved Fastening Device” issued toScripps on Jul. 11, 1989; U.S. Pat. No. 4,894,060 entitled “DisposableDiaper With Improved Hook Fastener Portion” issued to Nestegard on Jan.16, 1990; U.S. Pat. No. 4,946,527 entitled “Pressure-Sensitive AdhesiveFastener And Method of Making Same” issued to Battrell on Aug. 7, 1990;and the herein before referenced U.S. Pat. No. 5,151,092 issued to Buellon Sep. 9, 1992; and U.S. Pat. No. 5,221,274 issued to Buell on Jun. 22,1993. The fastening system may also provide a means for holding thearticle in a disposal configuration as disclosed in U.S. Pat. No.4,963,140 issued to Robertson et al. on Oct. 16, 1990. Each of thesepatents is incorporated herein by reference. In alternative embodiments,opposing sides of the garment may be seamed or welded to form a pant.This allows the article to be used as a pull-on type diaper, such as atraining pant.

The diaper 20 may also comprise side panels 30. The side panels 30 maybe elastic or extensible to provide a more comfortable and contouringfit by initially conformably fitting the diaper 20 to the wearer andsustaining this fit throughout the time of wear well past when thediaper 20 has been loaded with exudates since the elasticized sidepanels 30 allow the sides of the diaper 20 to expand and contract. Theside panels 30 may also provide more effective application of the diaper20 because even if the diaperer pulls one elasticized side panel 30farther than the other during application, the diaper 20 will“self-adjust” during wear.

While the diaper 20 of the present invention preferably has the sidepanels 30 disposed in the second waist region 38, the diaper 20 may beprovided with side panels 30 disposed in the first waist region 36 or inboth the first waist region 36 and the second waist region 38. (As usedherein, the term “disposed” is used to mean that an element(s) of thediaper is formed (joined and positioned) in a particular place orposition as a unitary structure with other elements of the diaper or asa separate element joined to another element of the diaper.) The sidepanels 30 may be constructed in any suitable configurations. Examples ofdiapers with elasticized side panels are disclosed in U.S. Pat. No.4,857,067, entitled “Disposable Diaper Having Shirred Ears” issued toWood, et al. on Aug. 15, 1989; U.S. Pat. No. 4,381,781 issued toSciaraffa, et al. on May 3, 1983; U.S. Pat. No. 4,938,753 issued to VanGompel, et al. on Jul. 3, 1990; the herein before referenced U.S. Pat.No. 5,151,092 issued to Buell on Sep. 9, 1992; and U.S. Pat. No.5,221,274 issued to Buell on Jun. 22, 1993; U.S. Pat. No. 5,669,897issued to LaVon, et al. on Sep. 23, 1997 entitled “Absorbent ArticlesProviding Sustained Dynamic Fit”; U.S. Pat. No. 6,004,306 issued toRobles, et al. on Dec. 21, 1999 entitled “Absorbent Article WithMulti-Directional Extensible Side Panels”; each of which is incorporatedherein by reference.

The diaper 20 preferably further includes leg cuffs 32 which provideimproved containment of liquids and other body exudates. Leg cuffs mayalso be referred to as leg bands, side flaps, barrier cuffs, or elasticcuffs. U.S. Pat. No. 3,860,003 describes a disposable diaper whichprovides a contractible leg opening having a side flap and one or moreelastic members to provide an elasticized leg cuff (a gasketing cuff).U.S. Pat. Nos. 4,808,178 and 4,909,803 issued to Aziz et al. on Feb. 28,1989 and Mar. 20, 1990, respectively, describe disposable diapers having“stand-up” elasticized flaps (barrier cuffs) which improve thecontainment of the leg regions. U.S. Pat. Nos. 4,695,278 and 4,795,454issued to Lawson on Sep. 22, 1987 and to Dragoo on Jan. 3, 1989,respectively, describe disposable diapers having dual cuffs, includinggasketing cuffs and barrier cuffs. In some embodiments, it may bedesirable to treat all or a portion of the leg cuffs with a lotion, asdescribed above.

Embodiments of the present invention may also include pockets forreceiving and containing waste, spacers which provide voids for waste,barriers for limiting the movement of waste in the article, compartmentsor voids which accept and contain waste materials deposited in thediaper, and the like, or any combinations thereof Examples of pocketsand spacers for use in absorbent products are described in U.S. Pat. No.5,514,121 issued to Roe et al. on May 7, 1996, entitled “Diaper HavingExpulsive Spacer”; U.S. Pat. No. 5,171,236 issued to Dreier et al. onDec. 15, 1992, entitled “Disposable Absorbent Article Having CoreSpacers”; U.S. Pat. No. 5,397,318 issued to Dreier on Mar. 14, 1995,entitled “Absorbent Article Having A Pocket Cuff”; U.S. Pat. No.5,540,671 issued to Dreier on Jul. 30, 1996, entitled “Absorbent ArticleHaving A Pocket Cuff With An Apex”; and PCT Application WO 93/25172published Dec. 3, 1993, entitled “Spacers For Use In Hygienic AbsorbentArticles And Disposable Absorbent Articles Having Such Spacer”; and U.S.Pat. No. 5,306,266, entitled “Flexible Spacers For Use In DisposableAbsorbent Articles”, issued to Freeland on Apr. 26, 1994. Examples ofcompartments or voids are disclosed in U.S. Pat. No. 4,968,312, entitled“Disposable Fecal Compartmenting Diaper”, issued to Khan on Nov. 6,1990; U.S. Pat. No. 4,990,147, entitled “Absorbent Article With ElasticLiner For Waste Material Isolation”, issued to Freeland on Feb. 5, 1991;U.S. Pat. No. 5,062,840, entitled “Disposable Diapers”, issued to Holtet al. on Nov. 5, 1991; and U.S. Pat. No. 5,269,755 entitled “TrisectionTopsheets For Disposable Absorbent Articles And Disposable AbsorbentArticles Having Such Trisection Topsheets”, issued to Freeland et al. onDec. 14, 1993. Examples of suitable transverse barriers are described inU.S. Pat. No. 5,554,142 entitled “Absorbent Article Having MultipleEffective Height Transverse Partition” issued Sep. 10, 1996 in the nameof Dreier et al.; PCT Patent WO 94/14395 entitled “Absorbent ArticleHaving An Upstanding Transverse Partition” published Jul. 7, 1994 in thename of Freeland, et al.; and U.S. Pat. No. 5,653,703 entitled“Absorbent Article Having Angular Upstanding Transverse Partition”,issued Aug. 5, 1997 to Roe, et al. All of the above-cited references arehereby incorporated by reference herein.

Embodiments of the present invention may also include a waste managementdevice 110 such as is shown in FIG. 2. The waste management device 110may include a waste bag 111 to collect feces, urine or both. The wastebag 111 may have an aperture 121 and a flange 112 surrounding theaperture for preferably adhesive attachment to the perianal area of awearer. Further, the waste management device 110 has been found to beparticularly useful and beneficial when used in conjunction with agarment, or diaper, preferably a disposable diaper. One example of adiaper 120 including a waste bag 111 is shown in FIG. 3. If associatedwith a diaper 120 or other garment, the waste bag 111 may be disposed onor joined to any surface of the article. The bag 111 may be joined tothe article by any known means, including any of the joining orattaching means described herein and/or any other joining means such asadhesive, hook and loop fasteners, magnetics, belts, ties, straps,snaps, etc. In one embodiment, the waste bag 111 is joined to thetopsheet 124 of the diaper 120.

The waste bag 111 is preferably a flexible receptacle for thecontainment of excreted fecal matter or urine. Thus, the waste bag 111is preferably liquid impermeable, and yet it may be breathable. Further,the waste bag 111 is designed of sufficient strength to withstandtypical wearing conditions, such as sitting.

The waste bag 111 may comprise one or multiple layers. In oneembodiment, the waste bag 111 may comprise three layers, preferably onefilm and two non-woven layers. The layers of the bag material maycomprise any material, preferably so that the bag is liquid impervious.In a preferred embodiment of the present invention a laminate may beformed from a non-woven layer and a film.

Suitable film materials for any of the film layers preferably comprise athermoplastic material. The thermoplastic material can may be vaporpervious or impervious and can be selected from among all types ofhot-melt adhesives, polyolefins especially polyethylene, polypropylene,amorphous polyolefins, and the like; material containing meltablecomponents comprising fibres or polymeric binders including naturalfibres such as cellulose—wood pulp, cotton, jute, hemp; synthetic fibressuch as fibreglass, rayon, polyester, polyolefin, acrylic, polyamid,aramid, polytetrafluroethylene metal, polyimide; binders such asbicomponent high melt/low melt polymer, copolymer polyester, polyvinylchloride, polyvinyl acetate/chloride copolymer, copolymer polyamide,materials comprising blends wherein some of the constituent materialsare not meltable; air and vapour permeable materials includingmicroporous films such as those described above with respect to thebacksheet and monolithic breathable materials such as HYTREL™ availablefrom DuPont and Pebax™ available from ELF Atochem, France.

The waste bag 111 may have any shape or size. Preferred shapes includeflat circular type bags, cone shaped bags, truncated cone shaped bagsand pyramidal or truncated pyramidal shaped bags and flat T shaped bags.Further, the waste bag 111 may be provided from a unitary piece ofmaterial or a number of separate pieces of material which may beidentical or different and which may be sealed at their respectiveperipheries.

The waste bag 111 may also contain absorbent material. The absorbentmaterial may comprise any absorbent material which is capable ofabsorbing and retaining liquids. The absorbent material may comprise awide variety of liquid-absorbent materials commonly used in disposablediapers and other absorbent articles. Some examples are described hereinwith respect to the absorbent core.

The waste bag 111 is provided with an aperture 121 whereby fecal matteror urine is received from the body prior to storage within the bagcavity. The aperture 121 is preferably surrounded by a flange 112 andmay be provided in any shape or size, such as circular, oblong, heartshaped and may be symmetrical or asymmetrical, preferably the aperturehas an oblong configuration either in the longitudinal or in thetransversal direction. The flange may comprise projections designed tofit the perineal, genital and/or coccygeal area of the wearer.

The flange 112 should be made of soft, flexible and malleable materialto allow easy placement of the flange 112 to the perianal or uro-genitalarea. Typical materials include nonwoven materials, wovens, open celledthermoplastic foams, closed-cell thermoplastic foams, composites of opencelled foams and stretch nonwoven, and films.

The waste bag 111 preferably farther comprises a joining or attachmentmeans to secure the device to the wearer. Such means may comprise any ofthe joining or attachment means described herein or any other suitablejoining or fastening means known in the art such as straps, belts, hookand loop fasteners, pins, ties, snaps and/or a body-compatible adhesiveapplied to the wearer facing portion of the waste bag 111 or the flange.Any skin-friendly water resistant pressure sensitive adhesive may beused to attach the device to the perianal or uro-genital area of thewearer, such as hydrocolloid adhesives and hydrogel adhesives.Particularly effective adhesives in providing the desired adhesiveproperties to secure the flange to the skin of the wearer at thesensitive perianal area, while allowing for relatively painlessapplication and removal, are formed from crosslinking polymers with aplastisicer to form a 3-dimensional matrix.

The diaper 20 may also comprise one or more “proactive sensors” 60. Asused in this application, the term “proactive sensor” refers to a sensoror sensor system that is capable of detecting or monitoring changes orsignals in or on the body of the wearer, in the article or in the waste,i.e., inputs, that directly relate or, at a minimum, correlate to theoccurrence of an impending event related to the bodily waste, thewearer, the article or a component or components thereof. Proactivesensors may respond to one or more specific inputs. Examples of inputsthat may be detected by a proactive sensor of the present invention inorder to predict an impending event include, but are not limited to,attitude, pressure, motion, vibration, sound, ultrasonic waves,electrical activity, contraction, tension, bloodflow, moisture,temperature, enzymes, bacteria, pH, conductivity, resistance,capacitance, inductance or other chemical, biochemical, biological,mechanical or electrical properties and/or components of bodily wastes.

The sensor 60, for example, may be chemical, mechanical, electrical,thermal, etc. A chemical sensor may respond to chemical and/orbiochemical inputs such as enzymes typically present in bodily wastes,pH, water, humidity or moisture, and/or biological inputs such asbacteria, blood or any other components of bodily wastes such as feces,urine, or menses, etc. Examples of chemical or biochemical sensorsinclude dissolving or rupturable films, capsules, cells, seals, etc.that dissolve or rupture in response to a specific chemical, biochemicalor biological input or to a specific class of chemical, biochemical orbiological inputs. A mechanical sensor may respond to motion, attitude,pressure, etc. An example of a mechanical sensor is a bellows-typesensor in which when the pelvic floor drops prior to defecation and thepressure pushes down on the bellows to inflate a portion of the sensor.A mechanical sensor may also include a sensor or a portion of the sensorthat is broken or separated under a pre-defined applied pressure. Anelectrical sensor may respond to moisture, urine, feces, menses,pressure, heat, temperature, conductance, resistance, capacitance,inductance, etc. An electrical sensor may, for example, include a sensorin which a conductive input such as urine completes an electricalcircuit; a sensor in which an input such as pressure, tension or heatcloses an electrical contact to complete a circuit; a piezoelectricsensor that generates a signal via pressure induced by the wearer or apart of the wearer (e.g., from motion or muscle tone); a piezoelectrictransducer that generates an ultrasonic wave when electrically triggeredand detects and/or compares “echo” returns, for example to measure thesize of a fluid-filled cavity such as the bladder or rectum; anultrasound imaging array; a sensor in which the resistance, capacitanceor inductance varies in the presence of the input to which the sensorresponds (e.g., conductance of the wearer's skin); or a sensor, such asan EMG sensor, that receives electrical signals from the body (e.g.,from the subcutaneous muscles) of the wearer through a contact such as askin contact sensor. A thermal sensor may be used to detect changes intemperature.

In yet another embodiment, the sensor may include one or more biosensorsas are known in the art (e.g., an enzyme sensor, organella sensor,tissue sensor, microorganism sensor, or electrochemical sensor). Thesensor may be adapted to detect proteins, sugars, bile components, etc.such as described in U.S. Pat. No. 4,636,474 entitled “ToiletApparatus,” issued to Kenji Ogura et al. on Jan. 13, 1987. Biosensorsmay comprise bio-recognition systems, typically enzymes or bindingproteins such as antibodies immobilized onto the surface ofphysico-chemical transducers. The biosensors may detect components ofbodily wastes, such as ammonia and phenol (e.g., via biosensorscomprising enzyme electrodes). A specific strain of bacteria may bedetected via biosensors employing antibodies raised against thatbacterial strain. Exemplary enzyme electrodes that may be used to detectphenols (e.g. in urine or feces) include tyrosinase based electrodes orpolyphenol oxidase enzyme electrodes described in U.S. Pat. No.5,676,820 entitled “Remote Electrochemical Sensor,” issued to JosephWang et al. on Oct. 14, 1997 and U.S. Pat. No. 5,091,299 entitled “AnEnzyme Electrode For Use In Organic Solvents,” issued to Anthony P. F.Turner et al. on Feb. 25, 1992, respectively.

The sensor of the present invention may be reversible or irreversible. Adissolving film or capsule is an example of an irreversible sensor,while an electrical sensor that receives electrical signals from thebody of a wearer which may receive multiple signals in succession is anexample of a reversible sensor.

A proactive sensor 60 may detect an impending event or detect aparameter that directly relates, or at a minimum correlates to theoccurrence of an impending event. An impending event that may bedetected or predicted by a proactive sensor 60 of the present inventionmay include, for example, urination, defecation, heat rash, skinirritation or rash, skin pressure marks, or an illness or medicalcondition of the wearer such as an internal infection (e.g., jaundice),a vitamin deficiency, a bile duct blockage, candidiasis, a parasite, apotential chronic skin condition or irritation, etc. A parameter thatcorrelates to an event is any measurable input, signal such as one ormore of the potential inputs listed above, that correlates with theoccurrence of the event within the frame of reference of the system(i.e., a signal caused by the waste or the wearer). The proactive sensor60 may, for example, predict the occurrence of a defecation, urinationor discharge of bodily waste or may detect signals that may precede skinrash or irritation. Proactive sensors 60 in an article may measure manydifferent inputs in order to predict an event. For example, theproactive sensor 60 may monitor the external anal sphincter muscle for acontraction or relaxation in the anal sphincter that precedes therelease of feces and/or urine; muscle activity in one or more of themuscles surrounding a body cavity such as the bladder, the colon or therectum; a separation of the buttocks; a pressure change in the abdomen;a gas concentration in the article; a drop in the pelvic floor; or anyother indication that may be used to predict or anticipate theoccurrence of an event such as a defecation, a urination or a dischargeof bodily wastes. Alternatively, a proactive sensor 60 of the presentinvention may detect signals that precede skin irritation. For example,the sensor may detect residual fecal contamination of the wearer's skin(e.g., fecal enzyme residue left on the wearer's skin after cleaning upa soiled diaper) that may, over time, lead to irritated skin. Detectionof a high pH, an increased skin hydration resulting in a measurableincrease in conductance or decrease in impedance of skin, a specificmicroorganism, fecal enzymes, etc. may also be used to predict potentialskin irritation.

The proactive sensor 60 may be disposed in and/or operatively connectedto any portion of a disposable article that will be exposed to the inputthat the sensor is designed to detect. For the purposes of the presentinvention, the term “operatively connected” refers to a means ofcommunication such that the proactive sensor 60 may signal some portionof the article 20 when the proactive sensor 60 detects an input. Theproactive sensor 60 may be separate from and operatively connected toanother portion of the article 20, another sensor 60, an actuator 70, acontroller 80 or some other component of the article 20. “Operativelyconnected” may, for example, include a means of communication such as anelectrical connection via a conductive wire or member, via a transmittedsignal such as radio frequency, infrared or another transmittedfrequency communication. Alternatively, the sensor 60 may be operativelyconnected via a mechanical connection such as a pneumatic or a hydraulicconnection.

In article 20, for example, the proactive sensor 60 may be located inthe front waist region 36, the rear waist region 38 or the crotch region37 of article 20, and may be integral with, disposed adjacent to, joinedto, or comprise a portion of the chassis 22, the topsheet 24, thebacksheet 26, the absorbent core 28, side panels 30, leg cuffs 32, awaist feature 34, a fastening system 40, the longitudinal 50 or end 52edges, etc. The proactive sensor 60 may be integral with the article 20,or may be installed by the caretaker or the wearer. The proactive sensor60 may be completely contained within the article such as article 20 ormay have a receiving portion located in the article such that it willcome into contact with the desired input and another portion such as atransmitting portion located either in the article or outside thearticle. Alternatively, the proactive sensor 60 may be external to thearticle 20 yet operatively connected to some portion of the article 20such that the proactive sensor 60 may detect an input external to thearticle 20 and provide a signal to a controller 80 and/or an actuator70. In some embodiments, the sensor may be separate from the article,e.g., separately applied to some portion of the wearer, and/or may haveone or more component separate from the article 20.

In one embodiment, the article 20 may include an extension 220comprising one or more sensors 60 as shown in FIG. 4. The extension 220may, for example, cover at least a portion of the wearer's abdomen,positioning the proactive sensor(s) 60, such as an EMG sensor, inproximity to the wearer's colonic or abdominal wall muscles. Theextension 220 may be of any suitable shape, size or material, may beelastic or inelastic, and may comprise a fastening system, stiffeningelements, or a body-adhering composition, such as a topical adhesive, tomaintain alignment of the sensor with the target muscles.

The proactive sensor 60 may preferably detect electrical activity in oneor more of the wearer's muscle groups, including the external analsphincter, external urethral sphincter, colonic muscles (i.e., smoothcolonic muscles), muscles of the abdominal wall, muscles surrounding thebladder, muscles surrounding the rectum or muscles associated with anyother body cavity or any bodily elimination. Alternatively, the sensor60 may measure the volume of the rectum, bladder or colon and signal thewearer or caregiver when the volume reaches a pre-defined threshold forthe individual. Although the actual volume of the bladder, rectum, colonor other body cavity may be measured, it may be more desirable tomeasure certain characteristics of the bladder or other body cavitywhich correspond to a certain volume. For example, it may be sufficientto measure the distance between the walls of the cavity, e.g. thebladder walls, and calculate or otherwise determine the approximatevolume of the cavity. Non-limiting examples of threshold values for thebladder or rectum which may be relevant to determining the nextexcretion include about 80% of daytime maximum volume or the minimumobserved micturition or defecation volume. More specifically, apre-micturition enuresis alarm for individual's having nighttime urinaryincontinence may signal the wearer or caregiver, for example, when thebladder reaches 80% of the maximum observed daytime bladder volume.Alternatively, the alarm can indicate when a predeterminedcharacteristic of the cavity (e.g. distance between bladder walls) ismet which corresponds to a particular volume of the cavity or whichcorresponds to imminent urination, defecation or other bodily activity.

The proactive sensor 60 may further comprise a sensing “system”including two or more sensors, each of which may detect the same ordifferent signals from the same or different sources. The sensing systemmay include components that are located inside, external to and/orseparate from the article. For example, the sensing system may include asensor inside the article that detects electrical signals in theexternal anal sphincter of the wearer and a sensor external to thearticle that detects motion, tension or muscle activity in the abdomenof the wearer. The sensing system may also or alternatively includecomponents other than the sensing elements inside, external to and/orseparate from the article. The sensing system, for example, may includea transmitter that is external to the article and transmits a signal toanother part of the sensing system that is joined to or disposed in thearticle 20. In yet other embodiments, the sensor 60 or sensing systemmay be part of a separate device which my be used together with orseparately from the article. For example, the sensing system may be acompletely independent device which can be configured to work inconjunction with an article such as a diaper or may be permanently ortemporarily integrated into such an article.

The article of the present invention may also comprise an actuator 70(see FIGS. 5 and 5A). As used in this application, the term “actuator”refers to a device that comprises “potential” and a means oftransforming that potential to perform or activate a “responsivefunction.” The potential of the actuator 70 may comprise either storedor potential energy or stored material. The actuator 70 thus may performor activate a responsive function by transforming potential energy tokinetic energy or by releasing or delivering a stored material. A“responsive function” is defined for the purposes of the presentinvention as a function performed upon the bodily waste, the wearer, thearticle, or a component or components thereof, or a signal to the weareror the caretaker. A component of bodily waste may include, for example,moisture, electrolytes, enzymes, volatile gases, bacteria, blood, etc. Acomponent of the wearer may also include skin, genitalia, the anus, theexternal anal sphincter muscle, etc. A component of the article may alsoinclude leg cuffs, waist cuffs or other waste barriers and/orcontainment components, side panels, ears, a chassis, an absorbent core,an acquisition component, a fastening system, the longitudinal or endedges, etc. Potential energy may be stored as mechanical, electrical,chemical or thermal energy. “Kinetic energy” as used in this applicationrefers to the capacity to do work or to perform a responsive function asdescribed above (e.g., expansion of a compressed device, rotation of atwisted device, a gel that moves as it changes phases, coating ortreatment of skin or feces, inhibition of an enzyme, adjustment of pH,etc.).

Triggering the creation of a three dimensional structure to capturewaste, for example, involves responsive functions performed on acomponent of the article and, ultimately, on the waste. Capturing waste,wiping the skin of the wearer, treating the feces with a feces modifyingagent, or treating the skin with a skin care composition, for example,are responsive functions performed on the waste and/or the wearer.Adjusting the article's geometry (in one, two or three dimensions) orphysical properties (e.g., bending modulus, geometry, etc.) are examplesof responsive functions, which may be performed on the article.Signaling a caretaker and/or the wearer that an event is about to occuror stimulating a portion of the wearer's anatomy are examples ofresponsive functions performed on the caretaker and wearer,respectively. An actuator of a disposable article may, for example,release or deliver a deodorant, enzyme inhibitor, skin care compositionor pH control agent; capture, wipe, cover, trap, immobilize, seal, pump,or store bodily waste; or trigger the release or creation of a structureor element designed to perform one or more of these functions or anyother responsive function upon the waste, wearer, article, or acomponent thereof.

An actuator 70 of the present invention may release potential energy toperform or activate a responsive function upon the waste, the wearer,the article, or a component thereof The release of potential energy maytransform mechanical, electrical, chemical or thermal potential energyinto mechanical, electrical or chemical kinetic energy to perform theresponsive function. Actuators may be triggered by a threshold level ofan input to release potential energy to perform a responsive function ormay respond continuously to an input as described below. For example, acompressed foam has stored compressive mechanical potential energy andmay provide mechanical kinetic energy when it is released. A twistedfoam has stored torsional mechanical potential energy that may providemechanical kinetic energy, i.e., rotation, when it is released. Inaddition, stored chemical, electrical or thermal energy may be used torelease electrical, mechanical, chemical or thermal kinetic energy. Anactuator of a disposable article, for example, may include one or moreof the following: stored lotion, feces modification agents, enzymeinhibitors, pH buffers, dyes, pressurized gas, a compressed foam, atwisted foam, a pump, a closed system liquid transport member, anelectrically sensitive gel, a pH sensitive gel, a salt concentrationgel, etc. Potential energy may be stored in any manner sufficient tomaintain/restrain it until it is required. Examples include batteriesand/or capacitors, elastically, torsionally, compressively tensionedmaterials or structures, in the form of unreacted reagents, andmaterials capable of performing physical or chemical functions (e.g.,absorbents, emollients, pH buffers, enzyme inhibitors, fecesmodification agents; compressed gases, etc.).

Alternatively, an actuator 70 of the present invention may comprise aquantity of a stored material that has the capacity to perform oractivate a responsive function upon the waste, the wearer, the article,or any component or components thereof. In one embodiment, for example,the actuator 70 may release or deliver a stored material that performs aresponsive function. In this embodiment, the actuator 70 may betriggered by a threshold level of an input to discontinuously release ordeliver the stored material at a given time or may release or deliverthe material continuously. The actuator 70 may, for example, includestored lotion, skin care compositions, feces modification agents, enzymeinhibitors, pH buffers, dyes, etc. In certain preferred embodiments, thematerial may be delivered by an actuator 70 such as an expandingresilient material, a released high pressure gas, etc.

In one embodiment of a bodily waste isolation device 90, as shown inFIGS. 5 and 5A, the actuator comprises a compressed foam spacer 94vacuum sealed under a water soluble film 92 (e.g., a PVA film). Uponreceipt of the proper signal from the proactive sensor, the actuatorcloses a switch that releases a small amount of stored water to contactand dissolve the water soluble film. This results in the release of thestored mechanical energy in the compressed foam. The foam expands andforms a spacer to provide void volume for the incipient feces.Alternatively, the switch closure may release two, chemicals thatcombine and create a foaming system, which may protectively coat theskin and/or engulf the feces when excreted. Similar systems to preparefor imminent urination events are also included in the scope of thisinvention.

In other embodiments, the responsive system may include an actuator thatalerts the caretaker or the wearer of an impending event such as adefecation or a urination. If the responsive system alerts thecaretaker, for example, the caretaker may prepare to change the articleto minimize the amount of time that the bodily waste is in contact withthe skin of the wearer, may ensure that a bedpan or an absorbent articleis in place to contain the bodily waste when it is eliminated, or mayaid the wearer in getting to the bathroom before the elimination of thebodily waste. If the responsive system alerts the wearer, the responsivesystem may act as a signaling device that alerts the wearer of animpending defecation or urination before the actual event. In anotherembodiment, the responsive system may actually stimulate a portion ofthe wearer's anatomy in response to the system's sensing of theimpending event. Thus, the responsive system can, for example, stimulatethe wearer to contract the urethral or anal sphincter muscle prior to animpending defecation or urination. This may provide the wearer withenough time to make it to a toilet or to fit him or herself with anappropriate absorbent or other waste receiving article prior to thewaste actually leaving the body.

Alternatively, the sensor and/or actuator may comprise a closed systemliquid transport member. A “closed system liquid transport member” or“transport member” comprises a liquid filled member having an inlet portand outlet port, which upon receipt of even a little amount of liquid atthe inlet port practically immediately releases liquid at the outletport. The liquid released from the outlet port may serve as an inputsignal to a sensor. For example, the liquid may be water, which isreleased when the transport member imbibes urine at an inlet port, whichacts to dissolve a seal to release stored mechanical energy to create afeces void space. Alternatively, the transport member may itself triggeran actuator (e.g., mix with agents to perform a chemical reaction), ormay perform at least a portion of the actuator function (e.g., thereleased water is imbibed by a super absorbent polymer arranged in aparticular geometry, which swells and forms a feces void volume). Liquidtransport through such transport members is based upon direct suctionrather than on capillarity. The liquid is transported through a regioninto which no significant quantity of air (or other gas) may enter. Thedriving force for liquid flowing through such a member can be created bya liquid sink (e.g., a capillary or osmotic absorbent structure) orsource in liquid connection with the member. Thus, a liquid transportmember must have a relatively high liquid permeability.

There are preferably at least two regions within the transport memberwith different pore sizes, namely the one or more port region(s) havingsmaller pores and the inner region having a much larger pore size. Theinner region of transport member has a permeability that is relativelyhigh compared to the permeability of a port region (a higher liquidpermeability provides less flow resistance), which can be a part of anouter/wall region circumscribing the inner/bulk region. Nonlimitingexamples of high porosity materials suitable for use as the inner regionmaterial include fibrous structures comprising polyolefin, PET,cellulose, and cellulose-based fibers, and porous, open celled foam suchas reticulated foams, cellulose sponges, polyurethane foams, and HIPEfoams. In one embodiment, the voids of the inner region are essentiallycompletely filled with an essentially incompressible fluid. The term“essentially completely” refers to the situation, where sufficient voidvolume of the inner region is filled with the liquid such that acontinuous flow path between inlet and outlet ports can be established.

The port regions of the transport member comprise materials which arepermeable for the transport liquid, but not for the ambient gas (likeair) once they are wetted with the transport liquid. Often, suchmaterials are described as membranes, which are defined as regions thatare permeable for liquid, gas or a suspension of particles in a liquidor gas. The membrane may for example comprise a microporous region toprovide liquid permeability through the capillaries. In an alternativeembodiment, the membrane may comprise a monolithic region comprising ablock-copolymer through which the liquid is transported via diffusion.Exemplary membranes for the port regions include celluloseacetatemembranes, such as also disclosed in U.S. Pat. No. 5,108,383 entitled“Membranes For Absorbent Articles” issued to White on Apr. 28, 1992, PETfilms as disclosed in EP-A-045 1797, nitrocellulose membranes,cellulosenitrate membranes, PTFE membranes, polyamide membranes, andpolyester. Other suitable materials are woven polymeric meshes, such aspolyamide or polyethylene meshes as available from Verseidag inGeldern-Waldbeck, Germany, or SEFAR in Rüschlikon, Switzerland.

The actuator 70 may alternatively comprise an electrically sensitivegel. Electrically sensitive gels are polymeric gel networks that, whenat least partially swollen with water, change volume and/or geometryunder the application of an electric current or field. For example,certain partially ionized polyacrylamide gels will undergo anisotropiccontraction of about 50% under weak electric fields (e.g., 0.5 volts/cm)when immersed in acetone and water. Alternative electrically sensitivegels may undergo electrically induced bending in the presence of waterand a surfactant or may undergo an oscillating wave motion whensubjected to an oscillating electric field. It is believed that localshrinkage may be induced in a portion of the gel, e.g., one side of agel element, by concentrating positively charged surfactant molecules onthe negatively charged gel polymer in an electric field. Changing theintensity and/or the polarity of the field induces a movement in the gelas one side decreases in length (e.g., a gel formed in a strip maycurl). Electrically sensitive gels may comprise variable geometries suchas rectangular, circular, reticulated grid, etc. patterns in order toprovide a valve to release a material, allow a bodily waste to flowthrough, prevent a bodily waste from flowing through, encapsulate abodily waste, etc. as they change volume and/or geometry. Anelectrically sensitive gel formed in a strip, for example, may be bentto provide an available void space for when electrical activity in theexternal anal sphincter muscle predictive of defecation or urination isdetected. In FIGS. 6A and 6B, for example, a strip of electricallysensitive gel 494 is shown in a circuit in which fecal moisture maybridge the contacts 485 and allow current to flow from battery 487 tothe electrically sensitive gel 494 either bending or straightening thestrip. Alternatively, an electrically sensitive gel 594 formed in areticulated grid pattern, such as shown in FIGS. 7A, 7B and 7C, may beelectrically induced to swell or shrink when an imminent urination isdetected to form a valve that allows and/or prevents urine flow toanother portion of the article 20. FIG. 7A, for example, shows a circuitincluding a reticulated grid pattern of an electrically sensitive gel.FIGS. 7B and 7C further show a microscopic view of the grid in a shrunk593 and in a swelled 595 configuration, respectively. An exemplarymaterial is a weakly cross-linked PAMPs gel (poly(acrylamido-2-methylpropane) sulphonic acid). This type of gel may perform various functionssuch as applying or delivering a chemical feces treatment agent. Otherexemplary electrically sensitive gels are described in U.S. Pat. No.5,100,933 issued to Tanaka on Mar. 31, 1990 and WO 9202005.Alternatively, pH sensitive gels or salt concentration sensitive gelsthat change volume and/or geometry at specific pH or saltconcentrations, respectively, may be used as an actuator of the presentinvention.

The actuator 70 may be disposed in and/or operatively connected to anyportion of disposable article that will allow the actuator to perform aresponsive function upon the bodily waste, the wearer, the article, or acomponent thereof. In article 20, for example, the actuator 70 may belocated in the front waist region 36, the rear waist region 38 or thecrotch region 37 of article 20, and may be integral with, disposedadjacent to or joined to a component of the chassis 22, the topsheet 24,the backsheet 26, the absorbent core 28, side panels 30, leg cuffs 32, awaist feature 34, a fastening system 40, the longitudinal 50 or end 52edges, etc. The actuator 70 may also be completely contained within thearticle such as article 20, may have a portion located in the articleand a portion located outside the article 20, or may be completelyexternal to the article 20. An actuator 70 or a portion of an actuator70 may be operatively connected to one or more sensors 60, one or morecontrollers 80, another portion of the actuator 70 or another portion ofthe article 20. Further, the actuator 70 may be integral with thearticle 20, or may be installed by the caretaker or the wearer.

The article 20 may also include a controller 80. A “controller” isdefined for the purposes of this application as a device that receivesan input from a sensor and determines if one or more actions are to betaken. The controller may receive a signal from the sensor 60 and directthe actuator 70 to perform a responsive function upon the bodily waste,the wearer, the article or a component thereof Alternatively, theactuator 70 may receive the signal directly from the sensor 60 andperform a responsive function upon the wearer, the waste, the article ora component thereof. A controller may include materials that undergochemical or physical change, may be a chemical, mechanical or electricaldevice that processes information from a sensor, etc. For example, in anarticle having a compressed plastic foam material encapsulated andrestrained under vacuum by a moisture soluble bag, the sensor 60 maycomprise the moisture soluble bag. The physical and chemicalcharacteristics of the film, i.e., the type of polymer, the thickness,etc., that determine how much of the input must be present before thefilm will dissolve act as the controller 80 and determine the thresholdlevel of input that must be met before the controller 80 allows theactuator 70 to release stored energy to perform a responsive function.The actuator 70 is the combination of the compressed foam and the lossof vacuum, which allows release of the stored mechanical energy of thecompressed foam. In this example, the controller 80 acts as a one-timeswitch. An electrical controller 80 that receives signals from thesensor 60 such as electrical activity of muscles of the wearer, however,may receive and monitor multiple electrical signals and may repeatedlytrigger the actuator. The controller may be integral with the sensorcomponent, integral with the actuator component, or a separate componentof the system.

The controller 80 may be disposed in and/or operatively connected to anyportion of a disposable article that will allow the controller 80 toreceive a signal from the sensor 60 and to provide a signal to theactuator 70. In article 20, for example, the controller 80 may belocated in the front waist region 36, the rear waist region 38 or thecrotch region 37 of article 20, and may be integral with, disposedadjacent to or joined to the chassis 22, or a component of the topsheet24, the backsheet 26, the absorbent core 28, side panels 30, leg cuffs32, a waist feature 34, a fastening system 40, the longitudinal 50 orend 52 edges, etc. The controller 80 may be integral with the article20, or may be installed by the caretaker or the wearer. The controller80 may be completely contained within the article such as article 20,may have a portion located in the article and a portion located outsidethe article, or may be located completely outside the article 20. Acontroller 80 or a portion of a controller 80 may be operativelyconnected to one or more sensors 60, one or more actuators 70, anotherportion of the controller 80 or another portion of the article 20. Thecontroller 80, for example, may receive a signal from the sensor 60 andprovide a signal to the actuator 70, e.g., by a radio frequency (rf)transmission.

Although distinct structural elements may perform the sensor 60,actuator 70 and controller 80 functions, the sensor 60, actuator 70and/or controller 80 functions of the present invention need not beperformed by distinct structural elements. The sensor 60 and controller80 functions, for example, may be performed by the same structuralelement such as a film that dissolves in contact with a component of abodily waste. In this example, the film acts as a sensor and responds tothe input component of bodily waste. The physical and chemicalcharacteristics of the film, i.e., the type of polymer, the thickness,etc., that determine how much of the input must be present before thefilm will dissolve act as the controller and determine the thresholdlevel of input that must be met before the controller allows theactuator to release stored energy to perform a responsive function.

A “responsive system” is defined for the purposes of this application asa system that includes a sensor 60 and an actuator 70 that acts upon thebodily waste, the wearer, the article, or a component or componentsthereof when the sensor 60 detects the appropriate triggering input.Upon sensing a given input parameter, the actuator 70 effects therelease of stored energy or the release or delivery of stored materialto perform a responsive function. When the proactive sensor 60 detectsan impending event, the actuator effects the release of stored energy.By detecting an input signal prior to the impending event, a responsivesystem in the article may be triggered to prepare for the event or tosignal the caregiver or the wearer of the impending event. This allowsconstruction of articles in which the waste-management technology isinitially “hidden” or unobtrusive, but which is available at, or justbefore, the moment of need and/or in which the article may provide thecaregiver or the wearer the opportunity to prepare for an event inadvance. Regardless of the specific input, the proactive sensor 60 inthese embodiments may trigger an actuator to perform an action on thearticle, the wearer or the environment to prepare for the occurrence ofthe event or provide a signal to the caregiver that the impending eventis about to occur. For example, if an impending defecation or urinationis to be detected via the electrical activity of the external analsphincter muscles, the system is preferably triggered (i.e., theresponsive system is activated) by a signal related to the reflexivecontraction of or the relaxation of the anal sphincter. The actuator maythen perform a function such as treating the wearer's skin to prevent orminimize skin irritation; preparing a bodily waste management device byactivating a fecal void spacer; opening a valve to allow urine to flowinto a storage device; releasing an enzyme inhibitor, skin carecomposition, pH control agent, or other skin treatment aids as known inthe art; or providing an audible, tactile, or visual warning signal tothe caregiver or the wearer. If the sensor 60 comprises a sensingsystem, one actuator may be triggered by different sensors and/orsignals, or different actuators may be triggered by different sensorsand/or signals. Alternatively, one sensor and/or signal may triggermultiple actuators.

A responsive system may respond in either a “continuous” or a“discontinuous” manner. As used in this application, a “continuousresponsive system” refers to a responsive system in which the output isquantitatively dependent upon the quantity of the input, i.e.,continuously increasing quantities of the input are required to effectcontinuously increasing quantities of the output, or where the output ofthe responsive system comprises a passive release of a stored material.A super absorbent polymer placed in an absorbent core of an article, forexample, provides a continuous response in which the output isquantitatively dependent upon the quantity of the input, i.e., asincreasing quantities of liquid waste contact the super absorbentpolymer, an increasing amount of the polymer contains that liquid untilthe capacity of the polymer is exhausted. A stoichiometric chemicalreaction is another example of a system having a continuous response toincreasing output. In the reaction A+excess B→C, for example, the amountof excess B converted to C is stoichiometrically and, therefore“continuously,” related to the amount of A available in the system. Oneexample of a continuous responsive system in which an inflatable spacerinflates to provide a void volume to store feces via a stoichiometricchemical reaction when a liquid such as urine contacts a gas evolvingmaterial, i.e., a continuous responsive system, is described in U.S.Pat. No. 5,330,459 entitled “Disposable Absorbent Article Having AnInflatable Spacer,” issued to Gary D. Lavon et al. on Jul. 19, 1994.Another example of a continuous responsive system in which a disposablearticle that improves the fit on the wearer by a liquid such as urinedissolving a film to release a leg cuff that has been held in anexpanded state is described in U.S. Pat. No. 4,246,900 entitled “DiaperIncluding Moisture-responsive Seal Means,” issued to Schroder et al. onJan. 27, 1981. A responsive system that passively releases a storedmaterial, however, generally provides a continuous response regardlessof how the material itself is released because the actual responsivefunction performed upon the bodily waste, the wearer, the article, or acomponent thereof is performed by the material, not by the release ofthe material. Thus, whether the material is released continuously inresponse to a given input, or released discontinuously at a single timewhen a threshold of a given input is detected, the responsive functionperformed by the released material is performed such that continuouslyincreasing quantities of the input are required to effect continuouslyincreasing quantities of the output until the material released isexhausted.

A “discontinuous responsive system” of the present invention, however,refers to a responsive system that has an output function that isessentially independent of the quantity of the input beyond a thresholdlevel. For example, when one or more threshold levels of a given inputare met, the responsive system may release all or a pre-designatedportion of its stored energy or deliver, i.e., actively transport, allor a pre-designated portion of its stored material to perform a specificresponsive function. In an ideal embodiment of the present invention,the output function, f(x), includes a “step” function as shown in FIG.8A. In this embodiment, the rate of change in the output with increasinglevels of input (d(output)/d(input)), i.e., the slope or firstderivative f′(x) of the. output function f(x), is preferably essentiallyzero when the amount of input is above or below the threshold level. Atthe threshold level, however, the d(output)/d(input) rate of changepreferably approaches infinity. Thus, in the ideal discontinuousresponse, the limit of the function f(x−ε) as ε→0 is not equal to thelimit of the function f(x+ε) as ε→0, i.e., lim f(x−ε)≠lim f(x+ε).

ε→0 ε→0

The present invention, however, recognizes that in the physical world anideal instantaneous step change at the threshold level is not necessaryand may not even be possible in many instances. In a preferredembodiment, it is only necessary that the output function have a virtualstep change with very little change in the input at or around thethreshold level of the input. Thus, the present invention contemplates adiscontinuous responsive system of the present invention having anoutput function that responds in a sufficiently discontinuous manner inthe transition region such that the output function has at least aminimum relative degree of steepness in the transition region. While notwishing to be limited to a particular method of describing or modeling adiscontinuous system, in a preferred method of determining whether agiven output function performs in a sufficiently discontinuous manner asdefined for the purposes of the present invention, the slope of theoutput curve at the inflection point is compared with the relative slopeof a line between the first and last points of the transition region.For example, FIG. 9A shows a graph of an exemplary output function, f(x)along with aligned graphs of the first, f′(x), and second, f″(x), andthird, f′″(x), derivatives of the exemplary output function. The outputfunction f(x) describes the effect of the in put (x or I) on the outputor response (R(I)). For purposes of the present invention, thetransition region is defined as the region between the relative maxima,R(I₁), and the minima, R(I₂), of the second derivative, f″(x), of theoutput function, f(x). The relative maxima, R(I₁), and the relativeminima, R(I₂), are points at which the third derivative, f′″(x), equalszero. The inflection point, I₀, is defined as the point in thetransition region at which the second derivative, f″(x), equals zero,i.e., ${\frac{^{2}R}{I^{2}}\begin{matrix}\begin{matrix}| \\|\end{matrix} \\{| I  = I_{0}}\end{matrix}} = 0.$

The comparison of the slope of the output function at the inflectionpoint to the slope of a line between the first and the last points ofthe transition region can be described by the equation:${\frac{R}{I}\begin{matrix}\begin{matrix}| \\|\end{matrix} \\{| I  = I_{0}}\end{matrix}} = {k{\frac{( {\Delta \quad R_{T}} )}{( {\Delta \quad I_{T}} )}.}}$

In this equation dR/dI at the inflection point is the first derivativeof the output function at that point. The term ΔI_(T) is the change inthe input to the responsive system between the first, I₁ and last, I₂,points of the transition region, i.e., I₂−I₁, and the term Δ R_(T) isthe change in the response of the output function between the first andlast points of the transition region, i.e., R(I₂)−R(I₁). The coefficientk is a proportional constant that describes the relative steepness ofthe slope of the output function at the inflection point, I₀, comparedto the slope of a line between the first and last points of thetransition region. In order that the responsive system have adiscontinuous output function, the proportional constant k must be atleast about 2.0, preferably at least about 3.0, more preferably at leastabout 5.0, even more preferably at least about 10.0, with at least about100.0 being the most preferred.

In certain embodiments, the relative degree of steepness in thetransition region of a discontinuous responsive system may also bemodeled by a transfer function of a control system having a series of aninteger number, n, first order lags with an equal time constant. Thetransfer function of the responsive system is defined for the purposesof the present invention as the ratio of the Laplace transforms of theoutput (responding variable) to the input (disturbing variable). See,e.g., Robert H. Perry & Don Green, Perry's Chemical Engineers' Handbook,Sixth Ed., Chap. 22 (McGraw Hill, Inc. 1984). As shown in FIG. 9B, therelative degree of steepness of an output function may be approximatedby the formula: KG(s)=K/(Ts+1)^(n) in which KG(s) is the transferfunction, K is a proportional element, T is the time constant of thesystem, and n is the integer number of first order time lags. In thismodel, as the number n increases, the steepness of the output functionin the transition region increases, and the model begins to approximatea discontinuous responsive system. Certain discontinuous responsivesystems of the present invention preferably may be modeled by the aboveformula when n is greater than or equal to about 25, with n beinggreater than or equal to about 50 being more preferred, and n beinggreater than or equal to about 100 being the most preferred.

As shown in FIG. 8A, a responsive system of the present invention mayinclude a single threshold level at which the responsive system mayrelease all of its stored energy to perform a specific responsivefunction or may include multiple threshold levels at which the systemmay release a pre-designated portion of its stored energy to perform oneor more specific responsive functions at each of the threshold levels.In an embodiment having a single threshold level, for example, theresponsive system may release all of its stored energy to perform theentire responsive function when that threshold level is met. In such asingle threshold embodiment, In this example, the discontinuousresponsive system includes a system that has two states such as on oroff. When a threshold quantity of an input such as bodily waste ispresent in the absorbent article, the responsive system may perform asingle responsive function upon the waste, the wearer, the article or acomponent thereof, such as enveloping the waste away from the skin ofthe user. Thus, the discontinuous responsive system may perform aone-time “switch-like” function that changes from one state to anotherin the presence of a threshold level of an input.

Alternatively, as shown in FIG. 8B, the responsive system may havemultiple threshold levels such as I_(t) 1 and I_(t) 2 at which when eachthreshold level is met the system may release a given “quanta” of energyor deliver a given quantity of material to perform a specific responsivefunction. In this embodiment, when each threshold level is met, aportion of the entire responsive function may be performed and/ordifferent independent responsive functions may be performed in responseto different threshold levels being met. For example, a responsivesystem may monitor a fecal enzyme and when each threshold enzyme levelis met may deliver an equal or unequal quantity of enzyme inhibitor(s)or lotion, or deliver a pH buffer at the first threshold level andperform another responsive function such as delivering a quantity ofenzyme inhibitor(s) at the second threshold level. In each transitionregion, the responsive system responds essentially the same as thetransition region in the single threshold embodiment described above.

In addition, a responsive system may monitor multiple inputs such asmoisture and/or one or more fecal enzymes and perform one or moreresponsive functions when the threshold levels of the different inputsare met or may perform one responsive function only when two or more ofthe threshold levels of the different inputs are met. Thus, a controllermay monitor multiple different inputs and perform a different responsivefunction when the threshold level of the different inputs are met.Alternatively, the controller may perform a logic OR-gate type functionsuch that a responsive function may be performed when one or morethreshold levels of the multiple inputs are met. The controller may alsoperform a logic AND-gate type function such that a responsive functionmay be performed when each threshold level of two or more differentinputs is met.

The responsive system may also comprise a “closed loop” or an “openloop” system. A “closed loop” system, which is also referred to as a“feedback control loop” system, includes distinct sensor 60 and actuator70 components and performs a responsive function upon the input. In somepreferred embodiments, the system may also use a detection or ameasurement of an element or a parameter of the output condition as atleast one trigger of the responsive function that is performed upon theinput. The output condition may be the state of the input conditionafter the actuator 70 has had the opportunity to perform a responsivefunction on the input condition. For example, if the sensor 60 ismonitoring the hydration level of the skin and the hydration levelreaches a threshold level, i.e., the output condition of the responsivesystem, the responsive system may release a predetermined quantity of adesiccant to bring the hydration of the skin back to the desired targethydration or hydration range or may release a desiccant until thehydration returns to the target hydration or the hydration range. Anabsorbent material such as a super absorbent polymer that continuallyabsorbs a liquid input until the liquid has all been absorbed or thecapacity of the polymer has been reached, however, is not considered tocomprise a closed loop system because the absorbent material does nothave distinct sensor 60 and actuator 70 components. The responsivefunction may be performed when the output condition reaches a thresholdlevel, or may be performed only when the output condition and one ormore other conditions are met. Acting upon the input may include actingupon the element sensed, e.g., sensing pH and acting upon the pH, or mayinclude acting upon a composition of which the element sensed is anintegral component, e.g., sensing a fecal enzyme or fecal moisture andacting upon feces. As described above, a feedback control loop systemincludes at least two distinct components: the sensor 60 and theactuator 70. The sensor 60 detects an event, or a parameter associatedwith that event. The actuator 70 receives a signal and performs aresponsive function on the input condition detected by the sensor 60.The feedback control loop may further include a controller 80. In thiscase, the sensor 60 may provide a signal to the controller 80, and thecontroller 80 may direct the actuator 70 to perform a responsivefunction upon the input condition. The controller 80 may be a separatecomponent of the responsive system or the controller function may beperformed by the sensor 60 and/or the actuator 70.

A preferred embodiment of a closed loop control system of the presentinvention comprises an electrical sensor capable of detecting changes inthe magnitude of electrical activity of sphincter muscles, particularlythe external anal sphincter, related to imminent release or thepotential for release of bodily waste and a means to deliver anelectrical impulse (or electrical stimulation) as required to theperianal skin of the wearer to induce a temporary contraction of thesphincter muscle to function as a continence aid. (This process may bealternatively referred to as dynamic graciloplasty nerve stimulation inthe medical literature.) For the purpose of this invention, theelectrical activity herein referred to as the electrical activity of theexternal anal sphincter may additionally include electrical activityfrom other muscles, including, but not limited to, pelvic floor musclesassociated with the external anal sphincter, or other muscles such asthe external urethral sphincter, the muscles of the colon, the musclessurrounding the bladder or the rectum or other muscles associated withelimination of waste from the body. Optionally, a visible, audible,and/or tactile (i.e., vibrating) signal is delivered to the wearerand/or caregiver, alerting them of the potential for waste elimination.

The electrical impulse may consist of one or more pulses of electricityor may be a continuous impulse. While the maximum strength of theelectrical impulse may be as high as about 35 volts, the electricalimpulse preferably has a voltage in the range of about 0.05 to about 5Volts and more preferably in the range of about 0.3 to about 1 Volt.Preferably, the electrical impulse current is in the range of about 0.1to about 100 mA. Preferably, the stimulation frequency is in the rangeof about 10 to about 100 Hz, more preferably in the range of about 20 toabout 80 Hz, and even more preferably in the range of about 60 to about80 Hz. If the impulse is a pulse (one or a multiplicity of pulses), theduration of each pulse is preferably in the range of about 0.1 to about5 ms and more preferably in the range of about 0.5 to about 1 ms. Incertain embodiments where the impulse comprises a multiplicity ofpulses, the entire set of pulses, or “pulse train”, may have a durationof about 0.1 second to about 15 seconds with an interval between pulsetrains of between about 1 second and about 60 seconds. Preferably, theelectrical stimulation voltage, frequency, the number and frequency ofpulses in a pulse train, and the number and duration of and spacingbetween pulse trains may be modified and/or controlled by the wearer orthe caregiver. Any electrical circuit as known in the art capable ofmeeting these parameters may be used to deliver or control theelectrical stimulation to the external anal sphincter or other bodylocation. For example, a 3 volt watch battery with a pulse generatingsystem may operatively connected with a proactive sensor, such as an EMGsurface electrode as described herein, and be used to deliver one ormore electrical impulses to the wearer's skin in the perianal region.One exemplary electrical stimulation device is the Prosper e.i.s. 5000system available from the Dr. Rowedder Biomedizinische Geraete inMuehbrook, Germany. This device may be alternatively used with anadhesive EMG surface electrode as described herein.

In alternative embodiments of stimulation (i.e., contraction) of theexternal sphincter muscles as a continence aid, the signal from thesensor may be directed to another site on the wearer's body to elicitthe anorectal reflex. For example, the sensor may trigger an electricalor mechanical stimulation of the perineal skin, the skin at the back ofthe wearer's knee, the sole of the foot, or any other site that resultsin the expression of the anorectal reflex.

The feedback control loop may be “non-modulating” or “modulating.” In a“non-modulating” feedback control loop responsive system the responsivesystem acts as a one-time switch in which the actuator performs aresponsive function on the input when the threshold level of the outputcondition is met. For example, the sensor 60 may detect a specificmicroorganism, and the actuator 70 may signal the caretaker of apotential incipient infection. In this example, the actuator 70 actsupon the input detected by the sensor 60. If the sensor 60 detectselectrical signals in the external anal sphincter of the wearer topredict an imminent defecation and the actuator 70 releases a compressedfoam material to create a shaped void of sufficient volume to containfeces, however, the actuator 70 acts upon something other than the inputdetected by the sensor 60, i.e., acts upon the feces instead of theelectrical activity in the sphincter muscles and is therefore not afeedback control loop. A “modulating” feedback control loop, however,includes a sensor 60, an actuator 70 and a controller 80. In amodulating feedback control loop, the output condition is monitoredconstantly or repeatedly, and the controller 80 directs the actuator toperform a responsive function on the input in order to maintain theoutput condition at a desired set point or within a desired range. Amodulating responsive system may constantly or repeatedly measuresphincter muscle electrical activity and send a signal to the sphinctermuscles to keep the anal sphincter closed for a desired period of timeto provide a feedback control loop responsive system.

An “open loop” system, however, is a system that responds to the inputto perform a responsive function without using feedback, i.e., theoutput has no effect upon the sensed input entering the system. An openloop system may include a responsive system that has a single devicethat performs the functions of both the sensor 60 and the actuator 70 ormay have distinct sensor 60 and actuator 70 components in which theactuator acts upon something other than the input. A super absorbentpolymer placed in an absorbent core of a disposable absorbent article,for example, provides an open loop response because the polymer onlyincludes a single device that performs the functions of the sensor 60and actuator 70. Alternatively, an open loop responsive system mayinclude a sensor 60 that detects bodily waste or a component of thatbodily waste, and an actuator 70 that performs a responsive function ina continuous or a discontinuous manner on something other than the inputdetected by the sensor 60. As above, for example, the sensor 60 maydetect sphincter muscle electrical activity, and the actuator 70 maycapture or store feces.

A block diagram of an exemplary open loop responsive system having asensor 60 and an actuator 70 is shown in FIG. 10A. A block diagram of analternative open loop responsive system including a sensor 60, anactuator 70 and a controller 80 is shown in FIG. 10C. A block diagram ofan exemplary closed loop responsive system having a sensor 60 and anactuator 70 is shown in FIG. 10B. A block diagram of an alternativeclosed loop responsive system including a sensor 60, an actuator 70 anda controller 80 is shown in FIG. 10D.

Other responsive systems are described in U.S. patent application Ser.Nos. 09/106,424 entitled “Disposable Article Having A DiscontinuousResponsive System” filed on Jun. 29, 1998, which has been allowed;09/107,563 entitled “Disposable Article Having A Responsive SystemIncluding A Feedback Control Loop” filed on Jun. 29, 1998, which hasbeen allowed; and 09/106,225 entitled “Disposable Article Having AResponsive System Including A Mechanical Actuator” filed on Jun. 29,1998 (P&G Case Number 7199), each of which is incorporated herein byreference.

An example of a diaper 20 of the present invention including a proactivesensor is shown in FIG. 1. In this embodiment, a skin contact sensorsystem comprises an electrical sensor 60 that includes three electrodes64, 65 and 66. An electrical sensor 60 of the present invention mayinclude two or more electrodes. In one embodiment, electrodes 64 and 65may be active and electrode 66 may be a reference electrode. This allowsfor a bimodal electrical pickup. The skin contact sensor system may bereleasably secured to the skin of the wearer in order to receiveelectrical signals from a muscle or muscle group of the wearer. Forexample, the skin contact sensor may be placed as close as possible tothe anus of the wearer so that the probe may detect signals from theexternal anal sphincter muscle, which is anatomically near the skin atthe point of the anal orifice. If the sensor is not self-adhesive, anelectroconductive, adhesive gel may be placed on the electrode of theskin contact probe before it is placed on the skin. In this embodiment,the skin contact sensors may be placed on the wearer by the caretaker,or may be integral with the article such that they are automaticallyaligned and attached to the wearer's skin near the anal perimeter whenthe article is placed on the wearer. A 7 mm adhesive disposable surfaceelectrode manufactured by Dantec Medical A/S of Skovlunde, Denmark,which may be connected to a Dantec EMG (Type 14 D11) receiver unit, forexample, is believed to be useful for the present invention. In thisexample, the Dantec EMG unit may be set, for example, at a time base of20 msec/division resulting in a screen sweep time of 0.2 seconds. Thegain amplifier may be set at 20 μV/division. A proactive sensor in thisembodiment may vary in size and manufacture and may optionally beintegral with the body of the article. The unit that receives the signalfrom the sensor(s) may be separate from the article or may be integralwith the article. If the receiver unit is separate from the article(i.e., a telemetry based system), the article may additionally comprisea transmitter to transmit the signal to the receiver. This may beaccomplished, for example, via an infrared (IR) or radiofrequency (RF)telemetry device. The settings for the sensor, transmitter (ifrequired), and receiver may vary according to the specific type ofsignal, sensor embodiment, and function to be performed.

The surface electrodes 64, 65 and 66 of the skin contact sensor systemin the above embodiment measure electrical signals in a muscle fiber ora group of muscle fibers. If the electrodes measure the electricalactivity of a group of muscle fibers, the total potential changeinvolves a greater mixture of frequencies. Preferably, the skin contactsensor or sensor system is capable of detecting electrical activitythroughout a frequency range including from about 5 Hz to about 500 Hz,and more preferably including from about 10 to about 350 Hz. Preferably,the electrodes utilize two active electrodes 64 and 65 and one referenceelectrode 66 for a bimodal electrical pickup. The electrical activitymeasured by the surface electrodes includes a combination of EMGsignals, other physiologic signals present on the skin surface such asEKG and electrodermal activity, and environmental artifacts such as 60Hz from electronic equipment or radio frequency interference. Whenbimodal electrodes are used in combination with a differentialamplifier, only those signals which are not detected in common by thetwo active electrodes are allowed to pass. Because a substantial portionof the common mode signals picked up by the electrodes are not EMGsignals, it may be advantageous to reject signals common to both activeelectrodes. This common mode rejection provides a cleaner, more discretesignal from the sensor.

In alternative embodiments, the electrical skin contact sensor of thepresent invention may be any other commercially available EKG(electrocardiogram) or EMG (electromyogram) electrode and/or measuringsystem. For example, the MyoTrace 200, available from Noraxon U.S.A.,Inc. of Scottsdale, Ariz., comprises a wideband electrode capable ofsensing muscle electrical activity in the 16 Hz to 500 Hz range (this isappropriate for the slow-twitch muscles of the pelvic floor). Anothercommercially available EMG sensing system is the MyoSense systemavailable from MIE Medical research Ltd., of Leeds, U.K. Other suitableadhesive surface electrodes include electrodes available from MedicotestA/S of Olstykke, Denmark as M-00-S, N-00-S, M-00-A/F, BS 3400, BS3500,BR, and BRS, as well as electrodes available from Multi Bio Sensor, Inc.of El Paso, Tex., as 3ST3, 3SG3-N, and 2DT2. Other suitable electricalsensors are disclosed in U.S. Pat. Nos. 5,785,040; 5,727,549; 5,337,748;5,203,330; 5,255,677, all of which are incorporated herein by reference.The electrodes of the present invention preferably comprise anelectrically conductive adhesive to maintain uninterrupted contact withthe wearer's skin.

In additional alternative embodiments of the present invention, thetelemetry system may be any commercially available EMG or EKG telemetrysystem. One suitable telemetry system is available from Noraxon U.S.A.,Inc. as the Telemyo system, comprising a battery-operated wearabletransmitter. Another suitable telemetry system is available from MIEMedical Research Ltd. as the MT8 Telemetry System. Another suitabletelemetry system is disclosed in U.S. Pat. No. 5,704,351.

For embodiments in which an imminent defecation or urination isdetected, the proactive sensor 60 may respond to a signal related toeither the reflexive contraction of or the relaxation of the externalanal sphincter, or to electrical activity in one or more of the musclessurrounding the rectum or bladder. In one embodiment of the presentinvention detect the contraction of the external anal sphincter as asignal of imminent or potential defecation. For example, in continentadults and older children and babies, the rapid filling of the rectumwith feces from the sigmoid junction (i.e., the lower region of thecolon) causes the external anal sphincter to reflexively (i.e.,involuntarily) contract. This reflex is referred to as the anorectalreflex. A sharp increase in the external anal sphincter muscle activityaccompanies the contraction of the external anal sphincter and isdetectable as an EMG signal via the sensors of the present invention.This reflex is absent in the newborn human infant and generally beginsto develop after about one year of age. Therefore, embodiments of thepresent invention intended to detect increased external anal sphincteractivity as a precursor of defecation may be generally more applicableto older babies (older than about 1 year of age). The increase inexternal anal sphincter electrical activity that signals rectal fillingis preferably at least about 2 times the basal external anal sphinctermuscle activity, but may be at least about 3 times the basal activity,at least about 5 times the basal activity or more.

In other preferred embodiments, the sensor detects sharp decreases in,or the absence of, the electrical activity of the external analsphincter. These decreases occur when the external anal sphincterrelaxes to open the rectal neck just prior to, or during, defecation.Generally, the electrical activity of the external anal sphincter musclewill drop sharply for at least several seconds as the muscles relax. Theactivity is at or close to zero immediately preceding and during theelimination process. In these embodiments, a sensor 60 may be triggeredby precipitous drops in muscle electrical activity, preferably drops ofgreater than or equal to about 50%. More preferably, the sensor 60 maybe triggered by drops of greater than or equal to about 75%, or equal toabout 95%.

Since muscular electrical activity is typically “noisy”, an averagedvalue of the amplitude (i.e., absolute value of the signal) should beused for comparison of the external anal sphincter activity undervarious conditions (e.g., basal state and stimulated conditions). FIG.11a is a graphical representation (Electrical Activity of Anal Sphincterv. Time) of a sharp increase in the external anal sphincter electricalactivity related to the extension of the rectum (i.e., for a normaladult) that is useful as a signal of imminent or potential defecation.The figure shows a basal sphincter muscle electrical activity level (a)followed by rectal filling which results in an increase in the magnitudeof electrical activity of the sphincter muscle related to the anorectalreflex (b). FIG. 11b is a graphical representation of a sharp decreasein the external anal sphincter electrical activity related to imminentor current defecation. The sphincter muscle activity during defecation(c) is shown between the anorectal reflex electrical activity (b) andthe basal electrical activity (a), which is typical.

Preferably, the target or “trigger” level of muscle electrical activityincrease or decrease that results in the signaling of the wearer orcaregiver or the application of an electrical stimulus may be varied orcontrolled by the wearer or caregiver based on differences betweenindividual wearers. In certain embodiments, one or more sequences ofelectrical stimuli to be delivered to a portion of the wearer's anatomy(e.g., the perianal skin) based on the particular detected muscleelectrical signal may be pre-programmed into a controller operativelyassociated with the sensor/actuator (i.e., stimulation device).

In one exemplary embodiment of the present invention, as shown in FIG.12, the article may comprise a belt 230 including at least one sensor 60to be fitted or secured around at least a portion of the wearer's lowerabdomen generally corresponding to the location of the transverse,descending, and/or sigmoid colon. At least a portion of the belt 230 maybe elastically extensible so as to accommodate local changes in thewearer's dimensions and to provide a sufficiently snug fit to hold thesensor 60 in the target location while the belt 230 is worn. The belt230 may be secured around the wearer's abdomen by any fastening systemas known in the art, including adhesive tapes, topical adhesives,mechanical fasteners such as hook and loop fasteners, buttons, and thelike. Any portion of the belt 230 or any of the sensors 60 mayalternatively be affixed to the wearer directly via the use of topicaladhesives or other body adhering compositions, which are described inmore detail below. In any case, at least one sensor 60, such as an EMGsensor, is preferably held in contact with the wearer's skin by the belt230. In embodiments having multiple sensors, it is generally preferredto have a multiplicity of sensors 60 contact the skin at intervals alonga path corresponding to at least a portion of the transverse, descendingand/or sigmoid colon.

Body adhering compositions suitable for use in the present invention maybe in any form, including, but not limited to gels, lotions, films, websor the like. Some exemplary body adhesives include adhesives, gelatin,petrolatum, waxes such as silicone or petroleum waxes, oils such assilicone or petroleum based oils, skin care compositions or ingredientsthereof Other topical adhesives include, but are not limited to,hydrogel or hydrocolloid adhesives such as acrylic based polymericadhesives, and the like. (Some exemplary hydrogel and/or hydrocolloidadhesives are disclosed in U.S. Pat. Nos. 4,231,369; 4,593,053;4,699,146; 4,738,257; and 5,726,250; each of which is incorporated byreference herein.) The topical adhesives may also include any “medicaladhesive” which is compatible for use with biological tissue, such asskin. Acrylic medical adhesives suitable for use as body adheringcompositions 80, include adhesives available from Adhesive Research,Inc., of Glen Rock, Pa., under the designations MA-46, MA-312, “MTTM”High MVTR adhesive, and AS-17. Rubber-based medical adhesives, such asSB-2 from Adhesive Research Inc. may also be suitable. Other exemplaryadhesives include Dow Corning Medical Adhesive (Type B) available fromDow Corning, Midland, Mich.; “MEDICAL ADHESIVE” from Hollister Inc., ofLibertyville, Ill.; 3M Spray Adhesives #79, 76, 77 and 90 available fromthe 3M Corp. of St. Paul, Minn.; and “MATISOL” liquid adhesive availablefrom Femdale Laboratories of Ferndale, Mich. Other medical adhesives aredescribed in U.S. Pat. Nos. 4,078,568; 4,140,115; 4,192,785; 4,393,080;4,505,976; 4,551,490; 4,768,503 and polyacrylate and polymethacrylatehydrogel adhesives are disclosed in U.S. Pat. Nos. 5,614,586 and5,674,275; the disclosure of each of which is incorporated by referenceherein. Yet another exemplary adhesive comprising polyvinyl pyrollidoneand a multi-functional amine-containing polymer is disclosed in WO94/13235A1. (The disclosure of each of these references is incorporatedherein by reference.) Alternative body adhering means which may be usedin place of or in addition to those described above include staticelectricity, suction and the like. In any case, it is preferred that thebody adhering composition permit vapors to pass (i.e., breathable), becompatible with the skin and otherwise skin friendly.

To obtain the desired characteristics, the body adhering composition maycomprise: from 0.5 to 20%, preferably 5% to 15%, by weight of amacromolecular polymeric substance or a mixture of such substancessoluble or swellable in the below mentioned plasticizer(s). As notlimiting examples such macromolecular or polymeric substances can benatural and/or synthetic such as natural gums or derivatives such asnatural gums and gelatins, their derivatives and alginates;polyacrylics; polyvinyl alcohol; polyethylene oxide; polyvinylpyrrolidon(PVP) or polyvinylethers, their copolymers and derivatives; cellulosederivative s; Block Copolymer Thermoplastic Elastomers and preferablyStyrenic block Copolymers and more preferably the hydrogenated gradesStyrol/Ethylene-Butylene/Styrol (SEBS), Styrene/Isoprene/Styrene (SIS),and Styrol/Ethylene-Propylene/Styrol (SEPS). Further, preferred bodyadhesive compositions may comprise from 45 to 99.5% by weight,preferably from 51 to 99.5% by weight, of a plasticizing substance or amixture of plasticizing substances, which are liquid at roomtemperature. As non-limiting examples the plasticizer can be water,various alcohols (like in particular glycerol), gylcols and theirethers, polyglycols, liquid polybutenes, esters such phtalates,adipates, stearates, palmitates, sebacates, or myristates, natural orsynthetic oils such as vegetable oils, mineral oils, or combinationsthereof Further, the body adhesive may include from 0% to 50% by weightof the composition, preferably 0% to 600% by weight of themacromolecular polymeric substance, of a tackifying resin whose mainscope is to tailor the Tg especially in systems based on syntheticpolymers. Also, preferred body adhesives may include from 0 to 10% andmore preferably from 0 to 5% by weight of substances for facilitatingand stabilizing the gel and the gel forming process both of hydrophilicor hydrophobic liquid plasticizers. These may be for oily systems, e.g.,the fatty acids of C₈ to C₂₂, their metallic salts and theirpolyoxo-derivatives; lanolin derivatives; silica; bentonite,montmorillonite and their derivatives; polyamides, waxes or mixturesthereof.

Common additives known in the art as preservative, antioxidants, antiUV, pigments, mineral fillers, rheology modifiers and the like can alsobe comprised in quantities up to 10% each. Also, when chemicalcrosslinks are formed in the system, a cross-linking agent can bepresent preferably in quantities up to 5% by weight. Chemicalcrosslinking can be formed also by mutual neutralization of polymershaving different functionalities as in the reaction between acidpolyacrylics and polysaccharides.

Suitable skin care compositions which may be used as, with, or in placeof the body adhesives include Category I actives as defined by the U.S.Federal Food and Drug Administration's (FDA) Tentative Final Monographon Skin Protectant Drug Products for Over-the-Counter Human Use, whichpresently include: alantoin, aluminum hydroxide gel, calamine, cocoabutter, dimethicone, cod liver oil (in combination), glycerine, kaolin,petrolatum, lanolin, mineral oil, shark liver oil, white petrolatum,talc, topical starch, zinc acetate, zinc carbonate, zinc oxide, and thelike. Other potentially useful materials are Category III actives asdefined by the U.S. Federal Food and Drug Administration's TentativeFinal Monograph on Skin Protectant Drug Products for Over-the-CounterHuman Use tentative final monograph on skin protectant drug products forover-the-counter human use, which presently include: live yeast cellderivatives, aldioxa, aluminum acetate, microporous cellulose,cholecalciferol, colloidal oatmeal, cysteine hydrochloride,dexpanthanol, Peruvian balsam oil, protein hydrolysates, racemethionine,sodium bicarbonate, Vitamin A, and the like. Many of the FDA monographedskin care ingredients are currently utilized in commercially availableskin care products, such as “A AND D” Ointment, “VASELINE” PetroleumJelly, “DESITIN” Diaper Rash Ointment and Daily Care Ointment, “GOLDBOND” Medicated Baby Powder, “AQUAPHOR” Healing Ointment, “BABY MAGIC”Baby Lotion, “JOHNSON'S ULTRA SENSITIVE” Baby Cream, Johnson's babylotion, lip balms, etc. Other suitable skin care compositions (e.g.,lotions) are described in detail in U.S. Pat. No. 5,643,588; U.S. Pat.No. 5,607,760; U.S. Pat. No. 5,609587; and U.S. Pat. No. 5,635,191; eachof these references being incorporated herein by reference.

In alternative embodiments of the present invention, one or more sensorsmay be arranged so as to detect patterns of high colonic muscleelectrical activity, “bursts”, which appear to travel from the proximalend of the transverse colon (i.e., near the hepatic flexure) along thecolon to the distal end of the descending colon (i.e., near therectosigmoid junction). These high amplitude electrical “spikes” or“bursts”, commonly termed “migrating long spike bursts” (“MLSBs”), or“Migrating Electrical Activity” are associated with progressivecontraction of the colonic muscles that creates a pressure wave alongthe colon, transporting the luminal contents of the colon, i.e., feces,to the rectum, where they become available for defecation. MLSBstypically have a duration of about 30 seconds, an amplitude of about 100to 500 μV, and a conduction velocity or approximately 15 mm/second andmay be detected at the skin surface using the EMG sensors positionedabove the colon. (A more detailed discussion of migrating long spikebursts can be found in the article entitled “Electromyography andManometry of the Pelvic Colon—a Contribution to the Understanding of itsFunction”, Medeiros, J. A., et al., Europ J Gastro Hepat vol. 8, pp.453-459 (1996), which is incorporated by reference herein.) The pressurewaves that move feces through the colon are commonly referred to a highamplitude propagating contractions or “HAPC”s. A graphicalrepresentation of the output from a sensor monitoring the electricalactivity associated with HPAC's over time is shown in FIGS. 13A-13F. TheMSLB's are designated 250 and are shown sequentially at predeterminedintervals as the contents of the wearer's colon are transported throughthe colon. In FIGS. 13A-13F, the horizontal axis represents the lengthof the colon from the cecum to the rectum as one moves from left toright on the axis. As the contents move through the colon, the signalmigrates toward the rectum. The output shown on the graphs 13A-13F issequenced such that the measurement depicted in FIG. 13B was takensubsequent to the measurement taken show in FIG. 13A, and so forth,through FIG. 13F. Thus, the Figures show a graphical representation ofthe movement of the colon's contents, as represented by a pressure wave,over time as one moves from FIG. 13A to FIG. 13F.

In one particular embodiment of the present invention, it has been foundthat a single sensor, such as an EMG sensor, located against the skin ofthe user in the general region of the sigmoid colon was capable ofdetecting electrical spikes as the contents of the colon were movedtoward the user's rectum. The Amplitude of the spikes was generallyfound to be in the range of about 40-100 μV, the frequency was found tobe in the range of about 0.1 Hz to about 10 Hz, and the duration was inthe range of about 5 to about 50 seconds. (It should be noted that theranges described above are only exemplary, and that the differentparameters could be monitored in different ranges, as desired. In justone example, the frequency of the spikes could be monitored in muchbroader range, such as from about 0.05 Hz to about 500 Hz and theAmplitude may be monitored at 10 μV or greater.) A graphical example ofthe output of the sensor 60 is shown in FIG. 14 and is designated 260,while representation of the pressure inside the colon associated withthe electrical activity is designated 270. As would be noted by one ofskill in the art, the units of the pressure 260 and electrical activity270 output would be different, but could be any suitable units, such asmmHg and μV, respectively.

In an alternative embodiment of the present invention in the form of apre-micturition enuresis alarm, the article may comprise a monitoringsystem including a piezoelectric transducer that measures the volume ofa fluid-filled cavity in the body, such as a bladder or rectum. Whenstimulated, the piezoelectric transducer sends an ultrasonic pulse intothe abdomen. The pulse may be sent out at any pre-defined or randominterval. The time delay or phase shift in the reflection of theultrasonic pulse by the various layers or components of the abdomen isthen detected by the transducer. The signal may be processed so as tocalculate the distance between the front and back walls of the bladderor other cavity and to estimate the e relative volume of the bladder orother cavity versus a reference state, such as a maximum observedvolume. When a predetermined threshold parameter is met, the systemsignals the wearer or caregiver or sends the information to anothersystem or device which stores the information or otherwise responds tothe input.

The piezoelectric transducer is preferably oriented appropriately so asto direct the ultrasonic pulse to the target cavity. In one suitableembodiment, the transducer has a frequency in the range of 3 to 5 Mz andis driven by an RF (radiofrequency) transmitter. A high-voltagehalf-wavelength pulse (e.g., a pulse of 45 to 80 Hz with a 30 nano-secrise time and a 150 non-second duty time) generates the ultrasoundburst. An exemplary piezoelectric transducer and associatedelectricavprocessing system suitable for use with the present inventionis described in more detail in the article “Design of a MiniaturizedUltrasonic Bladder Monitor and Subsequent Preliminary Evaluation on 41Patients”, Petrican, P., et al., IEEE Transactions on RehabilitationEngineering, Vol. 6, No.1, March 1998, which is incorporated byreference herein.

While particular embodiments and/or individual features of the presentinvention have been illustrated and described, it would be obvious tothose skilled in the art that various other changes and modificationscan be made without departing from the spirit and scope of theinvention. Further, it should be apparent that all combinations of suchembodiments and features are possible and can result in preferredexecutions of the invention. Therefore, the appended claims are intendedto cover all such changes and modifications that are within the scope ofthis invention. Also, although the present invention is illustrated anddescribed primarily with respect to a disposable diaper, the presentinvention is not limited to this embodiment. The present invention mayalso be used, for example, in articles that are applied directly to awearer (e.g., to the perianal or perineal regions of the wearer) priorto the application of a disposable diaper or in place of a disposablediaper, in a pull-on diaper, a diaper insert, a sanitary napkin, atampon, etc. It is therefore intended to cover in the appended claimsall such changes and modifications that are within the scope of thisinvention.

What is claimed is:
 1. A disposable article to be fitted to a wearer,the disposable article comprising: a sensor operatively connected to thearticle, the sensor being adapted to detect electrical activity in atleast one of the wearer's muscles, the electrical activity correlatingto an impending elimination of bodily waste; and to provide a signal tothe wearer, a caregiver or an element of the article of the impendingelimination.
 2. The disposable article of claim 1 wherein the sensor candetect the electrical activity of at least one of the wearer's smoothcolonic muscles, at least one of the wearer's abdominal muscles, atleast one of the muscles surrounding the wearer's bladder or at leastone of the muscles surrounding he wearer's rectum.
 3. The disposablearticle of claim 1 wherein the sensor can detect the electrical activityof at least one of the wearer's smooth colonic muscles, the Frequency ofthe electrical activity being between about 0.05 Hz and about 500 Hz. 4.The disposable article of claim 1 wherein the sensor can detect theelectrical activity of the wearer's smooth colonic muscles, theFrequency of the electrical activity being between about 0.1 Hz andabout 10 Hz.
 5. The disposable article of claim 1 wherein the sensordetects migrating electrical activity along the wearer's colon.
 6. Thedisposable article of claim 1 wherein the electrical activity of thesmooth colonic muscle is at least about 10 μV.
 7. The disposable articleof claim 1 wherein the electrical activity of the smooth colonic muscleis at least about 40 μV.
 8. The disposable article of claim 1 whereinthe sensor is located on the wearer's skin above at least a portion ofthe wearer's sigmoid colon.
 9. The disposable article of claim 1 whereinthe article is selected from the group including a belt, a diaper and anadhesive patch.
 10. The disposable article of claim 9 in the form of abelt, wherein the belt is at least partially elastic.
 11. The disposablearticle of claim 9 in the form of a diaper, wherein the diaper has anextension including the sensor.
 12. The disposable article of claim 1wherein the sensor includes an adhesive surface electrode which can beadhered to the wearer's skin.
 13. The disposable article of claim 1wherein the smooth colonic muscles have a basal electrical activitylevel and the sensor detects an increase in the electrical activity ofthe wearer's smooth colonic muscles of at least about three times thebasal electrical activity level of the smooth colonic muscles.
 14. Thedisposable article of claim 1 wherein the smooth colonic muscles have abasal electrical activity level and the sensor detects a decrease in theelectrical activity of the wearer's smooth colonic muscles of at leastabout 75% from the basal electrical activity.
 15. The disposableabsorbent article of claim 1 further comprising: (a) a topsheet; (b) abacksheet having a body-facing surface and a garment-facing surface, thebacksheet being joined to at least a portion of the topsheet; (c) anabsorbent core disposed between the topsheet and the backsheet.
 16. Thedisposable article of claim 1 wherein the disposable article includes awaste receiving device which is adhesively applied to the wearer tocollect feces or urine from an artificial stoma, the anus, or urethra.17. A disposable article to be fitted to a wearer, the disposablearticle comprising: a sensor operatively connected to the article, thesensor being adapted to detect when a body cavity of the wearer reachesa predetermined volume and; a signal mechanism which provides a signalto the wearer, a caregiver or an element of the article once thepredetermined body cavity volume is reached.
 18. The disposable articleof claim 17 wherein the body cavity is selected from the group includingthe rectum and the bladder.
 19. The disposable article of claim 17wherein the sensor includes a piezoelectric transducer and/or anultrasound scanner.
 20. The disposable article of claim 17 wherein thepiezoelectric transducer has frequency in the range of about 3 MHz toabout 5 MHz.
 21. The disposable article of claim 17 wherein the bodycavity has opposed walls and the sensor is adapted to detect a distancebetween the opposed walls of the body cavity.
 22. The disposable articleof claim 17 wherein the sensor correlates a particular distance betweenthe walls of the body cavity to a calculated body cavity volume.
 23. Thedisposable article of claim 17 wherein the article is a belt or adiaper.
 24. A method of assisting an incontinent person in achieving acontraction of his/her sphincter muscle, the method comprising thefollowing steps: a) identifying a specified electrical activity in amuscle associated with a body cavity of the incontinent person, theelectrical activity relating to an impending elimination of bodilywaste, b) monitoring the electrical activity of the muscle, c)determining whether the specified electrical activity has occurred; andd) providing a signal to the incontinent person that the electricalactivity has occurred.
 25. The method of claim 24 wherein the signal isone or more of the following: visual, aural or tactile.
 26. The methodof claim 24 wherein the signal is a stimulus to a portion of theincontinent person's anatomy to achieve a temporary contraction of thesphincter muscle.
 27. The disposable article of claim 24 wherein theelectrical activity includes one or more of the following: migratingelectrical activity along the wearer's colon, electrical activity in atleast one of the wearer's abdominal muscles, electrical activity in atleast one muscle surrounding the wearer's bladder and electricalactivity in at least one muscle surrounding the wearer's rectum.
 28. Themethod of claim 24 further including the step of providing theincontinent person with an waste receiving article.
 29. The method ofclaim 24 wherein the article is a diaper or a waste bag.